What about IBOC in USA ?
Zeldus
Hi evryone,
It's going to make years USA promised IBOC will work greatly and will be
operational soon. Today, we are in April 2002, nothing new about the
subject. When will we see a real commercial operational IBOC service working
somewhere in the world with commercial receivers available ? Is there any
experience of US listeners about IBOC ?
Is there a chance USA adopts Eureka 147 as most of the rest of the world did
before ?
Zeldus
Aztech
news:3ca82f04$0$5008$626a...@news.free.fr...
>
> Hi evryone,
>
> It's going to make years USA promised IBOC will work greatly and will be
> operational soon. Today, we are in April 2002, nothing new about the
> subject. When will we see a real commercial operational IBOC service working
> somewhere in the world with commercial receivers available ? Is there any
> experience of US listeners about IBOC ?
I guess it will follow the wild success of the American DTV standard - 8VSB/ATSC
http://www.economist.com/science/tq/displayStory.cfm?story_id=1020741
> Is there a chance USA adopts Eureka 147 as most of the rest of the world did
> before ?
Not unless DoD plans on giving up spectrum, broadcasters are also less than
happy about allowing new competition and sharing transmitters.
Az.
Steve
>
> It's going to make years USA promised IBOC will work greatly and will be
> operational soon. Today, we are in April 2002, nothing new about the
> subject. When will we see a real commercial operational IBOC service
working
> somewhere in the world with commercial receivers available ?
I've no idea. IBOC is a nice idea if it could work *properly*. IBOC cannot
offer new services because they can only fit the same signal and maybe a
small data channel in the bandwidth of the analogue service. They are just
going to re-transmit the analogue service so that when digital reception is
bad the receivers in cars can switch back to the analogue signal. Also,
digital signals cut off abruptly whereas analogue signals fade slowly and
because they're transmitting the digital signal at a low power level within
the analogue bandwidth the digital signal doesn't reach as far as the
analogue signal. Good in theory, probably pretty average in practice, at
least until they get round to switching off the analogue signals and then it
should be a lot better because they can use a higher power digital signal.
It seems like the rest of the world is going with DAB so IBOC might just be
a US thing.
> Is there any
> experience of US listeners about IBOC ?
>
> Is there a chance USA adopts Eureka 147 as most of the rest of the world
did
> before ?
No, they turned it down years ago in favour of the IBOC concept even though
trials in the US showed that DAB was far superior.
--
Steve
www.digitalradiotech.co.uk -- Compare DAB with digital radio via satellite
Aztech
"Steve" <in...@digitalradiotech.co.uk> wrote in message
news:a8a3j4$vtl$1...@newsg3.svr.pol.co.uk...
>
> "Zeldus" <n...@email.com> wrote in message
> news:3ca82f04$0$5008$626a...@news.free.fr...
> >
> > Hi evryone,
> >
> > It's going to make years USA promised IBOC will work greatly and will be
> > operational soon. Today, we are in April 2002, nothing new about the
> > subject. When will we see a real commercial operational IBOC service
> working
> > somewhere in the world with commercial receivers available ?
>
> I've no idea. IBOC is a nice idea if it could work *properly*. IBOC cannot
> offer new services because they can only fit the same signal and maybe a
> small data channel in the bandwidth of the analogue service. They are just
> going to re-transmit the analogue service so that when digital reception is
> bad the receivers in cars can switch back to the analogue signal. Also,
> digital signals cut off abruptly whereas analogue signals fade slowly and
> because they're transmitting the digital signal at a low power level within
> the analogue bandwidth the digital signal doesn't reach as far as the
> analogue signal. Good in theory, probably pretty average in practice, at
> least until they get round to switching off the analogue signals and then it
> should be a lot better because they can use a higher power digital signal.
>
> It seems like the rest of the world is going with DAB so IBOC might just be
> a US thing.
Yeah... it's a US thing, even Canada has gone Eureka147. IBOC is very spectrum
efficient if they manage to get it to work.
Az.
Nicolas Croiset
>> I've no idea. IBOC is a nice idea if it could work *properly*. IBOC cannot
>> offer new services because they can only fit the same signal and maybe a
>> small data channel in the bandwidth of the analogue service. They are just
>> going to re-transmit the analogue service so that when digital reception is
hello,
it's totally impossible to implement IBOC in Europe, because the
spectrum management is not the same as in the USA.
In the USA, the frequency plan have a step of 200 kHz, so it's
impossible to use frequency like 90.2 MHz for example. In europe the
frequency plan is 100kHz step. if you want to implement this technology
in europe you must suppress a lot of FM radio stations.
Bye.
Nicolas VDL diffusion - VDL soft
http://www.vdl.fr/
Kristoff Bonne
Steve <in...@digitalradiotech.co.uk> wrote:
> I've no idea. IBOC is a nice idea if it could work *properly*. IBOC cannot
> offer new services ...
Wasn't it designed _just_ to make sure no new services would be possible
that would disturbe the current market situation in the US. ;-)
> ... because they can only fit the same signal and maybe a
> small data channel in the bandwidth of the analogue service. ...
Euh. I am sorry, but I'm not very familiar with the US frequency-plan.
What exactly is the bandwidth of a FM station on the US? And, if there
is some place left for their digital system, why isn't it used nowdays.
It looks a bit daft to have (say) 200 Khz of bandwidth for your signal
and don't use it completely.
> ... Also,
> digital signals cut off abruptly whereas analogue signals fade slowly and
> because they're transmitting the digital signal at a low power level within
> the analogue bandwidth the digital signal doesn't reach as far as the
> analogue signal. ...
But you need less power to decode a digital signal then to receive a
analog signal. So, will this effect not mean that you can receive a
digital signal at the same distance, by using less power.
>> Is there any
>> experience of US listeners about IBOC ?
>> Is there a chance USA adopts Eureka 147 as most of the rest of the world
>> did before ?
> No, they turned it down years ago in favour of the IBOC concept even though
> trials in the US showed that DAB was far superior.
Well, trying NOT to start a round of America-bashing here; but I have
the impression that IBOC is a typical example of a system where
standards are defined by the industry and to few 'control' of the
gouvernement. IBOC is (IMHO) just there to maintain the current 'status
quo' in the broadcasting-industry. That digital broadcasting can
generate new applications for the users (like data-casting) and
more radio-stations (both more free radio-stations and more competition
between the different stations); is something which will probably go
unnoticed for the US people.
> Steve
Cheerio! Kr. Bonne.
Steve
news:pfmb8a...@frigg.belbone.net...
> Greetings,
>
> Steve <in...@digitalradiotech.co.uk> wrote:
> > I've no idea. IBOC is a nice idea if it could work *properly*. IBOC
cannot
> > offer new services ...
> Wasn't it designed _just_ to make sure no new services would be possible
> that would disturbe the current market situation in the US. ;-)
Probably.
> > ... because they can only fit the same signal and maybe a
> > small data channel in the bandwidth of the analogue service. ...
> Euh. I am sorry, but I'm not very familiar with the US frequency-plan.
>
> What exactly is the bandwidth of a FM station on the US? And, if there
> is some place left for their digital system, why isn't it used nowdays.
> It looks a bit daft to have (say) 200 Khz of bandwidth for your signal
> and don't use it completely.
It looks better than I thought, see the following paper:
http://www.nab.org/SciTech/Dab/Appendixb.pdf
96kbps, using AAC! Better audio quality than 192kbps DAB.
> Well, trying NOT to start a round of America-bashing here; but I have
> the impression that IBOC is a typical example of a system where
> standards are defined by the industry and to few 'control' of the
> gouvernement. IBOC is (IMHO) just there to maintain the current 'status
> quo' in the broadcasting-industry.
It certainly looks like it. Then again, if they transmit AAC at 96kbps and
assuming there isn't a high BER then it should be good.
> That digital broadcasting can
> generate new applications for the users (like data-casting) and
> more radio-stations (both more free radio-stations and more competition
> between the different stations); is something which will probably go
> unnoticed for the US people.
According to
http://www.economist.com/science/tq/displayStory.cfm?story_id=1020741
which is a good article, it says
"The company has designed a chipset that can not only process the old
analogue signal, but also combine it with two new digital streams. Moreover,
the digital broadcast was found to consume very little bandwidth, leaving
plenty of room for the fat analogue signal to spread its wings. In fact,
enough space was found in the saddle-bags to carry additional data. So,
apart from hearing local AM and FM with pin-sharp digital reception,
listeners can also get stock quotes, news headlines, weather forecasts, or
movie times on a display fitted in their car's dashboard. And if digital
reception is somehow obstructed, the IBOC chip can switch back to analogue,
which tolerates weak or reflected signals."
umar
>Wasn't it designed _just_ to make sure no new services would be possible
>that would disturbe the current market situation in the US. ;-)
IBOC will not be a success, I think. There's no consumer demand for it;
most radio listeners seem perfectly happy with AM and FM.
>What exactly is the bandwidth of a FM station on the US?
The FM band in the United States is divided into 100 channels spaced 200
kHz apart. Occupied bandwidth is limited to 150 kHz. In the northeast
(where I live/work), stations are spaced such that coverage is generally
limited by interference rather than by terrain or distance. Anything
that increases occupied bandwidth is only going to make that problem
worse.
>But you need less power to decode a digital signal then to receive a
>analog signal. So, will this effect not mean that you can receive a
>digital signal at the same distance, by using less power.
Not necessarily. One of the schemes being promoted for IBOC is a 10:1
high-power combiner, i.e. one that accepts inputs from a digital and an
analog transmitter on the same frequency but rejects 90% of the digital
power, sending only the remaining 10% to the antenna along with the
analog signal.
>Well, trying NOT to start a round of America-bashing here; but I have
>the impression that IBOC is a typical example of a system where
>standards are defined by the industry and to few 'control' of the
>gouvernement. IBOC is (IMHO) just there to maintain the current 'status
>quo' in the broadcasting-industry. That digital broadcasting can
>generate new applications for the users (like data-casting) and
>more radio-stations (both more free radio-stations and more competition
>between the different stations); is something which will probably go
>unnoticed for the US people.
Datacasting is overrated, in my opinion. With wideband mobile Internet i
access about to hit the market, who needs it?
umar
Aztech
news:pfmb8a...@frigg.belbone.net...
>
> Steve <in...@digitalradiotech.co.uk> wrote:
> > I've no idea. IBOC is a nice idea if it could work *properly*. IBOC cannot
> > offer new services ...
> Wasn't it designed _just_ to make sure no new services would be possible
> that would disturbe the current market situation in the US. ;-)
>
> > ... because they can only fit the same signal and maybe a
> > small data channel in the bandwidth of the analogue service. ...
> Euh. I am sorry, but I'm not very familiar with the US frequency-plan.
>
> What exactly is the bandwidth of a FM station on the US? And, if there
> is some place left for their digital system, why isn't it used nowdays.
> It looks a bit daft to have (say) 200 Khz of bandwidth for your signal
> and don't use it completely.
>
> > ... Also,
> > digital signals cut off abruptly whereas analogue signals fade slowly and
> > because they're transmitting the digital signal at a low power level within
> > the analogue bandwidth the digital signal doesn't reach as far as the
> > analogue signal. ...
> But you need less power to decode a digital signal then to receive a
> analog signal. So, will this effect not mean that you can receive a
> digital signal at the same distance, by using less power.
That doesn't really equate when you have to deal with appalling cross-channel
interference, I believe the Lucent system employs 4 x 32k streams distributed
across two sidebands, each stream progressively disappears when as the signal
gets weaker.
Az.
Richard Lambley
um...@world.std.com (umar) wrote:
> Datacasting is overrated, in my opinion. With wideband mobile Internet i
> access about to hit the market, who needs it?
People who don't want a packet counter running all the time they're using it?
Richard
--
R J Carpenter
>
> "Kristoff Bonne" <kristof...@compaqnet.nospam.be> wrote in message
> news:pfmb8a...@frigg.belbone.net...
> > What exactly is the bandwidth of a FM station on the US? And, if there
> > is some place left for their digital system, why isn't it used nowdays.
> > It looks a bit daft to have (say) 200 Khz of bandwidth for your signal
> > and don't use it completely.
Peak deviation in North America is 75 kHz, to which you have to add at
least the highest modulation frequency (first Besel sideband) of 15 kHz
- so the FM signal is 90 times two, 180 kHz broad. You will note that
with channel centers 200 kHz, these first-order sidebands nearly touch -
and there are higher-order Besel sidebands. The FCC has establushed a
"mask" and each FM station has to keep its sidebands and subcarriers
within that mask. Beyond 90 or 100 kHz away from channel center the
mask requires the signal to be 20 dB (just guessing) below the
unmodulated carrier. The IBOC digital signal is in the area limited by
the mask - and much of it is really lies in the first-adjacent FM
channel.
They say IBOC means In-Band-On-Channel, but I say it means In-Band
Off-Channel.
There are a couple of cases of FM stations in Washington, DC, and
Baltimore, MD, on first-adjacent channels (200 kHz apart). The cities
are about 35 miles apart. These are nominally 50 kW stations, but they
have directional antennas so there is much less power toward each
other. One of these stations was used for testing IBOC - but only one
of the pair - so it wasn't a real test of two IBOC stations on
first-adjacent channels.
Steve
news:3CAA40...@erols.com...
> Peak deviation in North America is 75 kHz, to which you have to add at
> least the highest modulation frequency (first Besel sideband) of 15 kHz
> - so the FM signal is 90 times two, 180 kHz broad. You will note that
> with channel centers 200 kHz, these first-order sidebands nearly touch -
> and there are higher-order Besel sidebands. The FCC has establushed a
> "mask" and each FM station has to keep its sidebands and subcarriers
> within that mask. Beyond 90 or 100 kHz away from channel center the
> mask requires the signal to be 20 dB (just guessing) below the
> unmodulated carrier. The IBOC digital signal is in the area limited by
> the mask - and much of it is really lies in the first-adjacent FM
> channel.
>
> They say IBOC means In-Band-On-Channel, but I say it means In-Band
> Off-Channel.
>
> There are a couple of cases of FM stations in Washington, DC, and
> Baltimore, MD, on first-adjacent channels (200 kHz apart). The cities
> are about 35 miles apart. These are nominally 50 kW stations, but they
> have directional antennas so there is much less power toward each
> other. One of these stations was used for testing IBOC - but only one
> of the pair - so it wasn't a real test of two IBOC stations on
> first-adjacent channels.
So are you rather sceptical of IBOC's future success then? What is its
bandwidth going to be? Do you think they will be able to transmit at 96kbps
and not interfere with the FM signal?
R J Carpenter
IIRC the information theorist Claude Shannon showed that, if you are
tricky enough, you can get almost any bit rate into any bandwidth - IF
THE SIGNAL TO NOISE RATIO IS GOOD ENOUGH. You see this every day with
your 50 kilobit per second modem working in a 2.5 kHz bandwidth phone
line. But only if you don't have a noisy phone line.
There is no question that 96 kbps can be piggy-backed on an FM channel.
The question is how robust it will be, and whether it will work when you
are out-of-sight of the transmitter (figuratively). I don't know the
answer to that question. My own guess is that car radios will revert to
analog quite a bit of the time. Then the question comes - HOW? I'd
expect that there would be a number of seconds of processing delay in
the digital receiver to carry through short outages (the satcasters do
this). How will the analog signal be delayed the same amount so the
switching back and forth will be seamless?
Bob C.
Kevin T.
> is some place left for their digital system, why isn't it used
> nowdays. It looks a bit daft to have (say) 200 Khz of bandwidth for
> your signal and don't use it completely.
The problem is that although North American FM stations are allocated
+/- 200 kHz of bandwidth for their signals, only +/- 100 kHz of it can
be used without overlapping onto adjacent channels. For example, if a
station on 96.1 MHz FM uses any more than +/-100 kHz of bandwidth, its
signal will overlap onto the signals of stations on 95.9 and 96.3 MHz.
This is no problem for regular analog FM because the bandwidth of an
ordinary analog FM Stereo signal is less than +/- 60 kHz. However, the
IBOC digital system places its digital data in the 130 to 200 kHz range.
While this still technically is okay by the FCC allocation of a +/- 200
kHz bandwidth for FM stations, in real-world use, it causes an
unacceptable amount of "bleed-over" onto adjacent channels, heard as a
hissing or buzzing noise. This has been heard in ALL cases where IBOC
has been tested on the FM band -- for example, when 102.7 WNEW-FM in New
York Ciy was testing IBOC, it was noticed that a loud buzzing noise was
heard on 102.5 and 102.9 MHz, blocking out reception of stations on
these channels!
This problem could be completely solved if IBOC signals did not leave
"room" for regular FM Stereo to be transmitted, and instead used this
spectrum space below +/- 100 kHz for the digital signal. This would
eliminate the adjacent channel interference problem at the expense of
only allowing the analog portion of the "hybrid" signal to be broadcast
with monaural sound.
Robert Orban
>
>
>> What exactly is the bandwidth of a FM station on the US? And, if there
>> is some place left for their digital system, why isn't it used
>> nowdays. It looks a bit daft to have (say) 200 Khz of bandwidth for
>> your signal and don't use it completely.
>
>The problem is that although North American FM stations are allocated
>+/- 200 kHz of bandwidth for their signals, only +/- 100 kHz of it can
>be used without overlapping onto adjacent channels. For example, if a
>station on 96.1 MHz FM uses any more than +/-100 kHz of bandwidth, its
>signal will overlap onto the signals of stations on 95.9 and 96.3 MHz.
>
>This is no problem for regular analog FM because the bandwidth of an
>ordinary analog FM Stereo signal is less than +/- 60 kHz. However, the
>IBOC digital system places its digital data in the 130 to 200 kHz range.
>While this still technically is okay by the FCC allocation of a +/- 200
>kHz bandwidth for FM stations, in real-world use, it causes an
>unacceptable amount of "bleed-over" onto adjacent channels, heard as a
>hissing or buzzing noise. This has been heard in ALL cases where IBOC
>has been tested on the FM band -- for example, when 102.7 WNEW-FM in New
>York Ciy was testing IBOC, it was noticed that a loud buzzing noise was
>heard on 102.5 and 102.9 MHz, blocking out reception of stations on
>these channels!
You are referring to first-adjacent channels, which are not assumed to
provide service under any circumstances in the presence of a strong
primary signal. In a given city, the FCC will generally allocate
third-adjacent frequencies (i.e., 600 kHz apart).
The FCC is not interested in FM DXers, but rather in providing service
according to their Table of Allocations. In practice, this means that
second-adjacent stations may be receivable on good radios even in the
presence of a strong signal. But first adjacents are not considered to be
usable, regardless of the quality of the receiver.
David Eduardo
"Kevin T." <kevtr...@yahoo.com> wrote in message
news:3CAA5F...@yahoo.com...
> > What exactly is the bandwidth of a FM station on the US? And, if there
> > is some place left for their digital system, why isn't it used
> > nowdays. It looks a bit daft to have (say) 200 Khz of bandwidth for
> > your signal and don't use it completely.
>
> The problem is that although North American FM stations are allocated
> +/- 200 kHz of bandwidth for their signals, only +/- 100 kHz of it can
> be used without overlapping onto adjacent channels. For example, if a
> station on 96.1 MHz FM uses any more than +/-100 kHz of bandwidth, its
> signal will overlap onto the signals of stations on 95.9 and 96.3 MHz.
100% modulation in the USA is +/- 75 kHz.
Steve
> Steve wrote:
> > So are you rather sceptical of IBOC's future success then? What is its
> > bandwidth going to be? Do you think they will be able to transmit at
96kbps
> > and not interfere with the FM signal?
>
> IIRC the information theorist Claude Shannon showed that, if you are
> tricky enough, you can get almost any bit rate into any bandwidth - IF
> THE SIGNAL TO NOISE RATIO IS GOOD ENOUGH.
I think you mean this:
C = B log2(1 + SNR)
But that doesn't apply to wireless channels because of fading. The above
equation assumes an AWGN channel such as phone lines.
> You see this every day with
> your 50 kilobit per second modem working in a 2.5 kHz bandwidth phone
> line. But only if you don't have a noisy phone line.
I don't know what your bandwidth is but in the UK I think it is 3.3kHz.
> There is no question that 96 kbps can be piggy-backed on an FM channel.
> The question is how robust it will be, and whether it will work when you
> are out-of-sight of the transmitter (figuratively). I don't know the
> answer to that question. My own guess is that car radios will revert to
> analog quite a bit of the time.
If that's the case it doesn't sound very good.
> Then the question comes - HOW? I'd
> expect that there would be a number of seconds of processing delay in
> the digital receiver to carry through short outages (the satcasters do
> this). How will the analog signal be delayed the same amount so the
> switching back and forth will be seamless?
Sounds tricky.
Steve
> > is some place left for their digital system, why isn't it used
> > nowdays. It looks a bit daft to have (say) 200 Khz of bandwidth for
> > your signal and don't use it completely.
>
> The problem is that although North American FM stations are allocated
> +/- 200 kHz of bandwidth for their signals, only +/- 100 kHz of it can
> be used without overlapping onto adjacent channels. For example, if a
> station on 96.1 MHz FM uses any more than +/-100 kHz of bandwidth, its
> signal will overlap onto the signals of stations on 95.9 and 96.3 MHz.
>
> This is no problem for regular analog FM because the bandwidth of an
> ordinary analog FM Stereo signal is less than +/- 60 kHz. However, the
> IBOC digital system places its digital data in the 130 to 200 kHz range.
> While this still technically is okay by the FCC allocation of a +/- 200
> kHz bandwidth for FM stations, in real-world use, it causes an
> unacceptable amount of "bleed-over" onto adjacent channels, heard as a
> hissing or buzzing noise.
Nightmare!
> This has been heard in ALL cases where IBOC
> has been tested on the FM band -- for example, when 102.7 WNEW-FM in New
> York Ciy was testing IBOC, it was noticed that a loud buzzing noise was
> heard on 102.5 and 102.9 MHz, blocking out reception of stations on
> these channels!
Ooops.
> This problem could be completely solved if IBOC signals did not leave
> "room" for regular FM Stereo to be transmitted, and instead used this
> spectrum space below +/- 100 kHz for the digital signal. This would
> eliminate the adjacent channel interference problem at the expense of
> only allowing the analog portion of the "hybrid" signal to be broadcast
> with monaural sound.
This sounds like a nightmare. You'll be in a chicken and egg situation where
there won't be sufficient digital radio receivers to make the FM stations
want to change the FM signal to mono but there's either buzzing on the
adjacent channels or too low a bit rate to provide decent quality audio.
Looks like XM and Sirius might do better than they'd have originally hoped.
R J Carpenter
> > IIRC the information theorist Claude Shannon showed that, if you are
> > tricky enough, you can get almost any bit rate into any bandwidth - IF
> > THE SIGNAL TO NOISE RATIO IS GOOD ENOUGH.
>
> I think you mean this:
>
> C = B log2(1 + SNR)
>
> But that doesn't apply to wireless channels because of fading. The above
> equation assumes an AWGN channel such as phone lines.
I suppose you could say it's accurate if the SNR you use is the worst
you see in the fades. But it isn't accurate anyway, because it assumes
white noise IIRC. Anyway, the FCC FM allocation plan has station
coverage limited by interference rather than weak signals in most
cases. And that's cochannel interference in many cases.
In the heavily populated part of the USA from Washington, DC, to Boston,
lots of stations came on with the original FM allocation plan which
allowed stations 400 kHz apart in the same general area, etc. Then the
FCC adopted a more strict plan with generally 600 or 800 kHz spacing in
the same area - but the old stations were generally grandfathered as
they were. What's more, they were allowed to increase power by 2.5 or 3
times. So we have full power (50 kW ERP at 152 m HAAT equivalent)
stations on 99.5 MHz in Washington, DC, Wilmington, DE, and New York
City. Wilmington is roughly 120 miles from DC and NYC. The same
situation exists on a number of other channels.
Kevin T.
> quality of the receiver.
Tell that to anybody who listens to FM in their car. I am actually
surprised to find how sensitive and selective most car radios are on FM
these days. So, many car radios will deliver a very decently listenable
signal from an FM station 40 to 60 miles away, even when sandwiched
right next to a strong local station. And considering the lack of
variety many people experience from their local stations, they *are*
tuning in to these more distant stations, even if they can only listen
to them in the car because no home or portable radio they have is good
enough to pick up these "unuseable" signals.
And people are also deluded if they think IBOC's digital audio will
sound better than analog FM. There is no question that hybrid stations
will use the same ear-bleeding Optimod-style processing and compression
on both their analog and digital audio. And if the experience of DAB in
Europe has taught us anything, it is that this kind of heavy audio
processing degrades the quality of "lossy" digital compression, such as
the MPEG upon which DAB and IBOC is based. IBOC is only using 96 kbps
which even with AAC is nowhere near "CD-quality", just as even at 192
kbps, the MPEG Layer 2 used by DAB is clearly inferior to direct
un-"lossy" audio.
Robert Casey
digital bandwidth to broadcast several audio programs within
the DTV channel. It's already in the specs of DTV to send
unrelated to TV data streams, i.e., digitized audio (radio).
Basically, it would just be an extension of the soundtrack
of the video. Just have more digital "soundtracks" without
video. Realize that analog TV sound is nearly equivalent
to an FM radio station. There's slight differences in the
technical specs, but anyone who lives in a city with a channel
6 knows you can hear the sound on an FM radio just below
88MHz.
David Eduardo
> > But first adjacents are not considered to be usable, regardless of the
> > quality of the receiver.
>
> Tell that to anybody who listens to FM in their car. I am actually
> surprised to find how sensitive and selective most car radios are on FM
> these days.
I love it. Frikkin' Kevin is arguing allocations, bandwidth and FM
allocations with Robert Orban.
Give up. AM stereo is dead.
>So, many car radios will deliver a very decently listenable
> signal from an FM station 40 to 60 miles away, even when sandwiched
> right next to a strong local station.
However, as Mr. Orban said, the allocations plan was not designed to provide
protection for serendipitous reception any more than it guarantees DXers in
the East reception of Class A stations from California. Nor was any
licensee, past or present, guaranteed protection for this type of reception.
> And considering the lack of
> variety many people experience from their local stations, they *are*
> tuning in to these more distant stations, even if they can only listen
> to them in the car because no home or portable radio they have is good
> enough to pick up these "unuseable" signals.
There is absolutely no evidence of this in radio ratings diaries. And
believe me, I have seen thousands and thousands and thousands and thousands.
(Before you say something about Arbitron, remember that every bit of
listening, including to satellite, out of market and adjacent signals gets
tabulated. If it meets MRS (Minimum Reporting Standards) it makes the
book... otherwise it is accessible via Maximiser by subscribers)
>
> And people are also deluded if they think IBOC's digital audio will
> sound better than analog FM.
I have taken part in one of Ibiquities hour-long tests at NAB last year and
also done the bus rides at other demonstrations. My opinion, based on being
a programmer and formerly an engineer is that the digital audio stream can
sound better than analog. All depends on how it is delivered to the
transmitter and processed.
At least it does not make me queasy like AM stereo did.
> There is no question that hybrid stations
> will use the same ear-bleeding Optimod-style processing and compression
> on both their analog and digital audio.
Some of the finest sounding stations, including classical music ones, have
Optimods. Actually, about every significant FM on the planet has one (except
for the few still using the Ford Taurus processor [anyone who has seen one
knows what I mean]). I just had 3 LA stations and two Phoenix ones put new
8400s on the air, and they are magnificent!
A processor is a lot like a car, where the proper use depends on the driver.
A car can do precision corners and be kept in optimum conditions... or used
to speed and run over pedestrians. An Optimod or even a Level Devil can be
made to sound very fine or very awful, depending on the station personnel.
Generally, unless there is a major defect, we do not sue the car maker when
a drunk driver wipes out another vehicle... don't blame Bob for what users
decide to do with his product.
> And if the experience of DAB in
> Europe has taught us anything, it is that this kind of heavy audio
> processing degrades the quality of "lossy" digital compression, such as
> the MPEG upon which DAB and IBOC is based.
Which is a responsibility of the station. They may find it appropriate to
trade some quality or dynamic range for loudness.
> IBOC is only using 96 kbps
> which even with AAC is nowhere near "CD-quality", just as even at 192
> kbps, the MPEG Layer 2 used by DAB is clearly inferior to direct
> un-"lossy" audio.
I'm so happy you can hear it. Most humans can't. You said you were a
Klingon, right?
Kevin, you are a lot like the jocks who needed a 1st Ticket back in the 60's
and 70's... they went to REI or some other quickie tickie school... and came
out proving that a little knowledge is actually dangerous. Legions or real
engineers can give testimony to the damage inflicted by these guys who
learned just enough to pass a test but thought they were actually qualified
to work on equipment and adjust DA systems.
Kevin T.
> allocations with Robert Orban.
And I love it that Frikkin' YOU, Mr. David Eduardo Gomez Noguera, are
wasting your time in these newsgroups.
> Give up. AM stereo is dead.
What does that have to do with anything besides the fact that you hate
AM Stereo so much, you love it? Obviously you are ashamed to admit that
you actually *LIKE* listening to AM Stereo, so you take it out by
bashing those who are not afraid to speak out about it! Otherwise, you
wouldn't be wasting your time talking about it here, would you? After
all, if it is "dead", then doesn't that mean you have absolutely no life
if you waste your time bitching and moaning about it?? I bet you also
go to the video newsgroups and pick fights with people who still like
VHS, or go to the computer newsgroups and pick fights with people who
still like OS/2!!
You remind me of people who HATE a certain radio program SO MUCH, they
LISTEN TO IT EVERY DAY, just to remind themselves of how much they HATE
it! And the hosts and producers of these programs laugh all the way to
the bank, because listeners are listeners and ratings are ratings,
regardless if the people listening "like" their program or not!
> There is absolutely no evidence of this in radio ratings diaries. And
> believe me, I have seen thousands and thousands and thousands and
> thousands.
Has it ever occured to you that the vast majority of radio listeners
have never been approached by Abritron, and that there are many radio
stations that have been on the air with a successful format with
thousands of loyal listeners, many dedicated advertisers, and a healthy
operating budget, and yet NEVER show up in the ratings, even over
DECADES of being on the air?
After all, if only stations that get good ratings were on the air, then
the AM and FM bands would suddenly be a LOT less crowded.... and then we
might actually be able to squeeze in these splattery IBAC (In-Band,
ADJACENT Channel) signals!
> My opinion, based on being a programmer and formerly an engineer is
> that the digital audio stream can sound better than analog.
Joselito and Magdalena won't think it sounds so good when the digital
sidebands of some IBOC signal are sqashing out reception of their
favourite FM "Ranchera Exitos" station....
> At least it does not make me queasy like AM stereo did.
Listening to "Dr. Laura" in thrilling monaural makes me physically sick.
But do I remind myself of that fact by listening to her every day and
then complaining about it to everybody who happens to be a fan of her
show? NO!! Because that would exactly fit the textbook definition of
somebody who needs to GET A LIFE.
That is what you need to do, Dah-veed, mi amigo... GET A LIFE (OBTENGA
UNA VIDA) and stop wasting your time by incessantly, hypocritically, and
passive-aggressively arguing against things that you claim you dislike,
but in reality you probably love to hate!
> Some of the finest sounding stations, including classical music ones,
> have Optimods.
Any commercial audio processor/squisher/mangler is the equivalent of a
bow and arrow. Using it properly is an exercise of skill and restraint,
while when it is used improperly, it can be a deadly weapon, regardless
of whose inflated ego (and inflated bank account) has his name printed
on the front panel.
> An Optimod or even a Level Devil can be made to sound very fine or
> very awful, depending on the station personnel.
And sounding "very fine" or "very awful" is entirely in the ears of
Joe Schmo the station engineer. He'll tune it up to sound "very fine"
on the $9.99 K-Mart radio in his 1984 Chevette, and for everybody else
it won't sound quite so great.
In Europe, DAB was designed to broadcast an UNPROCESSED signal, so that
the audio processing may be applied on the RECEIVER side, if the
listener so desires. However, most DAB stations are ignoring this, and
Billy-Bob Orban is all too happy to feed them with processors that let
them squish and mangle their audio to death, just as they do on FM, MW,
and LW.
> I'm so happy you can hear it. Most humans can't. You said you were a
> Klingon, right?
You offer no evidence to contradict the popular notion that most people
who work in the professional audio business are both hard of hearing and
tone-deaf. MAYBE I SHOULD TYPE IN ALL CAPS SO THESE PEOPLE CAN ACTUALLY
HEAR ME!
David Eduardo
> > I love it. Frikkin' Kevin is arguing allocations, bandwidth and FM
> > allocations with Robert Orban.
>
> And I love it that Frikkin' YOU, Mr. David Eduardo Gomez Noguera, are
> wasting your time in these newsgroups.
It seems we hit a nerve, huh, Kevin?
>
> > Give up. AM stereo is dead.
>
> What does that have to do with anything besides the fact that you hate
> AM Stereo so much, you love it? Obviously you are ashamed to admit that
> you actually *LIKE* listening to AM Stereo, so you take it out by
> bashing those who are not afraid to speak out about it! Otherwise, you
> wouldn't be wasting your time talking about it here, would you? After
> all, if it is "dead", then doesn't that mean you have absolutely no life
> if you waste your time bitching and moaning about it?? I bet you also
> go to the video newsgroups and pick fights with people who still like
> VHS, or go to the computer newsgroups and pick fights with people who
> still like OS/2!!
No, I will leave that to you. You do it oh-so-well with AM stereo.
I have only heard AM stereo a couple of times. On each occasion, I found it
slightly better than "regular" AM. However, wen presented with the vile
things it does on the frnge areas of AM signals, I recognized it for what it
was: a slight detriment to the listening to my station.
In that sense, I eliminated something that was neither used (no radios) or
useful (no appeal). End of my acquaintance with AM stereo.
>
> You remind me of people who HATE a certain radio program SO MUCH, they
> LISTEN TO IT EVERY DAY, just to remind themselves of how much they HATE
> it! And the hosts and producers of these programs laugh all the way to
> the bank, because listeners are listeners and ratings are ratings,
> regardless if the people listening "like" their program or not!
Actually, I have no beef with AM stereo, as nearly everyone on the planet
knows it is dead. However, the disinformation that you plant on these groups
is not helpful to this generation of radio folks, whether listeners or
professionals.
Since I often have a lot of time while moniitoring the stations I am
responsible for, I find it interesting, educational at times, and generally
entertaining to exchange viewpoints on these groups. I also spar with the
Hitler Youth on alt.politics.immigration, if you care. However, for a game
of rope-a-dope, you are uparalleled.
I still can't believe you took on Bob Orban, someoen who has done more for
the enhancement of radio engineering than nearly anyone I can think of in
the last several decades. It offends me that you dismiss him so lightly...
but I'm sure you could care less.
>
> > There is absolutely no evidence of this in radio ratings diaries. And
> > believe me, I have seen thousands and thousands and thousands and
> > thousands.
>
> Has it ever occured to you that the vast majority of radio listeners
> have never been approached by Abritron, and that there are many radio
> stations that have been on the air with a successful format with
> thousands of loyal listeners, many dedicated advertisers, and a healthy
> operating budget, and yet NEVER show up in the ratings, even over
> DECADES of being on the air?
No, it does not occur to me. Because a correctly designed random
probablility sample will show any any listening to any staiton that is above
ground clutter level. Obviously, statistics, like FM bandwidth and
modulation characteristics, are not your strong suit.
Anecdote: in Winter, 1979, a station went ont he air in San Juan. It
impacted so strongly that it went form nowhere to a 33.5 share in Mediastat
in Puerto Rico. Interestingly, Puerto Ricans travel a lot to visit family in
New York and vice versa around the holiday season, which ends after Three
Kings Day in January. That station in Puerto Rico showed up below the line
in the New York Arbitron that one time... because diarykeepers in NY had
visited the Island and listened.
And you say that Arbitron, or any similar sample, does not pick up such
happenings.
Stations that don't make the ratings do so because they do not have a
statistically significant number of listeners. Or they have none.
>
> After all, if only stations that get good ratings were on the air, then
> the AM and FM bands would suddenly be a LOT less crowded.... and then we
> might actually be able to squeeze in these splattery IBAC (In-Band,
> ADJACENT Channel) signals!
>
> > My opinion, based on being a programmer and formerly an engineer is
> > that the digital audio stream can sound better than analog.
>
> Joselito and Magdalena won't think it sounds so good when the digital
> sidebands of some IBOC signal are sqashing out reception of their
> favourite FM "Ranchera Exitos" station....
Who the hell are Joselito and Magdalena? Joselito was a bullfighter in Spain
in the 40's and Magdalena is the largest river in Colombia. This has exactly
what bearing on the trajectory of carrier pigeons in New York? Or anything
else?
>
> > At least it does not make me queasy like AM stereo did.
>
> Listening to "Dr. Laura" in thrilling monaural makes me physically sick.
> But do I remind myself of that fact by listening to her every day and
> then complaining about it to everybody who happens to be a fan of her
> show? NO!! Because that would exactly fit the textbook definition of
> somebody who needs to GET A LIFE.
Laura is not having a good year. But she stillhas a cume of several million,
which ain't bad for AM radio.
She will probably live without you... or any of us. I'm sure here retirement
is already funded. Yours proabably isn't.
>
> That is what you need to do, Dah-veed, mi amigo... GET A LIFE (OBTENGA
> UNA VIDA) and stop wasting your time by incessantly, hypocritically, and
> passive-aggressively arguing against things that you claim you dislike,
> but in reality you probably love to hate!
You only wish, as it woudl validate your points. Pssst!!!! HTis was about
your dissing of Bob Orban, not about AM stereo.
Folks like you are why I love AM talk radio... the caller who has pushable
buttons who will be a catalyst for the rest of the audience. Make for good
radio. Probably makes for good newsgroup, too.
>
> > Some of the finest sounding stations, including classical music ones,
> > have Optimods.
>
> Any commercial audio processor/squisher/mangler is the equivalent of a
> bow and arrow. Using it properly is an exercise of skill and restraint,
> while when it is used improperly, it can be a deadly weapon, regardless
> of whose inflated ego (and inflated bank account) has his name printed
> on the front panel.
>
> > An Optimod or even a Level Devil can be made to sound very fine or
> > very awful, depending on the station personnel.
>
> And sounding "very fine" or "very awful" is entirely in the ears of
> Joe Schmo the station engineer. He'll tune it up to sound "very fine"
> on the $9.99 K-Mart radio in his 1984 Chevette, and for everybody else
> it won't sound quite so great.
Actually, the standard is about a $30 dollar radio. Usually, we buy an
assortment of them, including a couple of boom boxes, a car radio at Pep
Boys, another from a junk yard,and a minicomponant or two. If you can find a
sound that will work well on that mix of radios, you probably will sound
good to 99% of the listeners on 99% of thier radios.
>
> In Europe, DAB was designed to broadcast an UNPROCESSED signal, so that
> the audio processing may be applied on the RECEIVER side, if the
> listener so desires. However, most DAB stations are ignoring this, and
> Billy-Bob Orban is all too happy to feed them with processors that let
> them squish and mangle their audio to death, just as they do on FM, MW,
> and LW.
When you find the perfect human board op, we can do without processing.
Until then, it is necessary to process to avoid saturation on one side and
sinking into the noise floor on the other. Excessive peaks in digital are
not very nice to hear. they are even ugly to see. Sorry, Kevin, but the only
input material that does not need some form of peak limiting and audio
processing is much of the wretched stuff that comes prekilled on CDs at your
own neighborhood record store... the source material itself is squished,
squashed and processed from here to the sampling rate and back.
And there you go with Bob Orban again. You really are a hateful person. At
first I just thought you were eccentric, but I have decided you are far
more. Steven King could write your biography.
>
> > I'm so happy you can hear it. Most humans can't. You said you were a
> > Klingon, right?
>
> You offer no evidence to contradict the popular notion that most people
> who work in the professional audio business are both hard of hearing and
> tone-deaf. MAYBE I SHOULD TYPE IN ALL CAPS SO THESE PEOPLE CAN ACTUALLY
> HEAR ME!
You, of course, have no more proof of this than you do of most of your other
statements. Your insistence in bashing Bob Orban was the final clue.
Golly, this was fun.
Your serve?
a...@redhat.invalid
>> > ... because they can only fit the same signal and maybe a
>> > small data channel in the bandwidth of the analogue service. ...
>> Euh. I am sorry, but I'm not very familiar with the US frequency-plan.
>>
>> What exactly is the bandwidth of a FM station on the US? And, if there
>> is some place left for their digital system, why isn't it used nowdays.
>> It looks a bit daft to have (say) 200 Khz of bandwidth for your signal
>> and don't use it completely.
> It looks better than I thought, see the following paper:
> http://www.nab.org/SciTech/Dab/Appendixb.pdf
> 96kbps, using AAC! Better audio quality than 192kbps DAB.
Last time I heard, the real IBOC rollout will use a version of
Lucent's PAC coder instead of AAC. AAC was used for the trials.
I may have been told wrongly, though: correction invited.
> And if digital reception is somehow obstructed, the IBOC chip can
> switch back to analogue, which tolerates weak or reflected signals."
Which says it all, really.
One great advantage of a hybrid system is that you can "spin the dial"
without having to wait for a receiver to synch with a station. If I
recall correctly, digital lock-on takes quite a long time with IBOC.
Andrew.
Peter Maus
David Eduardo wrote:
>
> "Kevin T." <kevtr...@yahoo.com> wrote in message
> news:3CAA8B...@yahoo.com...
> > > But first adjacents are not considered to be usable, regardless of the
> > > quality of the receiver.
> >
> > Tell that to anybody who listens to FM in their car. I am actually
> > surprised to find how sensitive and selective most car radios are on FM
> > these days.
>
> I love it. Frikkin' Kevin is arguing allocations, bandwidth and FM
> allocations with Robert Orban.
>
I think it's quite a testiment to the man's generosity that Mr. Orban actually
took the time to address Kevin. What's the adage? "No man stands taller than
when he stoops to help a child."
The telling in this thread, is that now, over the course of the last several
months, we've had on air marketing and promotions (me), Programming and
Promotions (you), and now Engineering (of all people Robert Orban!) all try to
get through to Kevin and he still won't take the message.
Which is: You can't make a change in Broadcasting, until you create a demand
in the public. Because Broadcasters, until they see money in it, can't be made
to care. And railing at Broadcasters for being deaf, dumb, blind, stupid or
lazy, isn't persuasive and won't make them change what they believe to be
working...Only a new profit center driven by public demand can do that.
And if you want any evidence of, call Programming at Clear Channel.
The history of Broadcasting in the United States IS this principle. It has
always been about money. EVEN NPR.
Short of an FCC mandate, if there ain't money in it, Broadcasters ain't
interested.
Steve
news:a8ekff$636$2...@hammerfield.cambridge.redhat.com...
> > 96kbps, using AAC! Better audio quality than 192kbps DAB.
>
> Last time I heard, the real IBOC rollout will use a version of
> Lucent's PAC coder instead of AAC. AAC was used for the trials.
> I may have been told wrongly, though: correction invited.
Okay, I think I read this on here recently aswell. BTW, which is best, PAC
or AAC?
> > And if digital reception is somehow obstructed, the IBOC chip can
> > switch back to analogue, which tolerates weak or reflected signals."
>
> Which says it all, really.
>
> One great advantage of a hybrid system is that you can "spin the dial"
> without having to wait for a receiver to synch with a station.
I don't get you?
> If I
> recall correctly, digital lock-on takes quite a long time with IBOC.
IBOC doesn't sound very good really.
Steve
> Steve wrote:
> >
> > "R J Carpenter" <rca...@erols.com> wrote in message
> > news:3CAA58...@erols.com...
>
> > > IIRC the information theorist Claude Shannon showed that, if you are
> > > tricky enough, you can get almost any bit rate into any bandwidth - IF
> > > THE SIGNAL TO NOISE RATIO IS GOOD ENOUGH.
> >
> > I think you mean this:
> >
> > C = B log2(1 + SNR)
> >
> > But that doesn't apply to wireless channels because of fading. The above
> > equation assumes an AWGN channel such as phone lines.
>
> I suppose you could say it's accurate if the SNR you use is the worst
> you see in the fades.
We were shown a way of using it last year which multiplied the SNR in the
equation by the Rayleigh fading gain and by the shadowing gain.
> But it isn't accurate anyway, because it assumes
> white noise IIRC.
Yes, this is what I said. AWGN means additive white Gaussian noise.
> Anyway, the FCC FM allocation plan has station
> coverage limited by interference rather than weak signals in most
> cases. And that's cochannel interference in many cases.
Sounds reasonable. That's how they do it for mobile comms systems.
> In the heavily populated part of the USA from Washington, DC, to Boston,
> lots of stations came on with the original FM allocation plan which
> allowed stations 400 kHz apart in the same general area, etc. Then the
> FCC adopted a more strict plan with generally 600 or 800 kHz spacing in
> the same area - but the old stations were generally grandfathered as
> they were. What's more, they were allowed to increase power by 2.5 or 3
> times. So we have full power (50 kW ERP at 152 m HAAT equivalent)
> stations on 99.5 MHz in Washington, DC, Wilmington, DE, and New York
> City. Wilmington is roughly 120 miles from DC and NYC. The same
> situation exists on a number of other channels.
Err, you've lost me here. :)
a...@redhat.invalid
> <a...@redhat.invalid> wrote in message
> news:a8ekff$636$2...@hammerfield.cambridge.redhat.com...
>> > 96kbps, using AAC! Better audio quality than 192kbps DAB.
>>
>> Last time I heard, the real IBOC rollout will use a version of
>> Lucent's PAC coder instead of AAC. AAC was used for the trials.
>> I may have been told wrongly, though: correction invited.
> Okay, I think I read this on here recently aswell. BTW, which is
> best, PAC or AAC?
Similar. Last I heard there were no independent test results.
>> > And if digital reception is somehow obstructed, the IBOC chip can
>> > switch back to analogue, which tolerates weak or reflected signals."
>>
>> Which says it all, really.
>>
>> One great advantage of a hybrid system is that you can "spin the
>> dial" without having to wait for a receiver to synch with a
>> station.
> I don't get you?
It taks quite a while for an IBOC receiver to acquire a station, so
you need the anlaog signal if you want to to spin the dial searching
for a station you like the sound of.
>> If I recall correctly, digital lock-on takes quite a long time
>> with IBOC.
> IBOC doesn't sound very good really.
How polite of you! :-)
Andrew.
Steve
news:9kwq8.6174$l32.392...@newssvr21.news.prodigy.com...
> > And people are also deluded if they think IBOC's digital audio will
> > sound better than analog FM.
>
> I have taken part in one of Ibiquities hour-long tests at NAB last year
and
> also done the bus rides at other demonstrations. My opinion, based on
being
> a programmer and formerly an engineer is that the digital audio stream can
> sound better than analog. All depends on how it is delivered to the
> transmitter and processed.
How high were the processing levels during this test? I would imagine that
being a test they would have left the Optimod processors off it.
> > There is no question that hybrid stations
> > will use the same ear-bleeding Optimod-style processing and compression
> > on both their analog and digital audio.
>
> Some of the finest sounding stations, including classical music ones, have
> Optimods. Actually, about every significant FM on the planet has one
(except
> for the few still using the Ford Taurus processor [anyone who has seen one
> knows what I mean]). I just had 3 LA stations and two Phoenix ones put new
> 8400s on the air, and they are magnificent!
He did say "ear-bleeding". Now I agree that you shouldn't blame Bob Orban
for the way his customers use his products but believe me that what
processing has gone on in the past on FM will not carry through to digital.
Take BBC Radio 1 in the UK. It is highly processed on FM but they have
lowered the processing levels because they were clashing with the MPEG
encoder. Processors lead to some frequency components becoming unmasked in
comparison with the original so you have a fundamental trade-off:
Processing level against audio quality
In future you won't be hearing ear-bleeding processing because I've
witnessed it and for all the arguments about people not caring about audio
quality, they will not listen to audio quality that is so bad that it is
unlistenable.
> A processor is a lot like a car, where the proper use depends on the
driver.
> A car can do precision corners and be kept in optimum conditions... or
used
> to speed and run over pedestrians. An Optimod or even a Level Devil can be
> made to sound very fine or very awful, depending on the station personnel.
> Generally, unless there is a major defect, we do not sue the car maker
when
> a drunk driver wipes out another vehicle... don't blame Bob for what users
> decide to do with his product.
I agree. But the processing levels will fall when digital properly takes
over. The *only* way to keep processing levels high would be to redesign the
MPEG encoder to specifically cater for processed audio.
> > And if the experience of DAB in
> > Europe has taught us anything, it is that this kind of heavy audio
> > processing degrades the quality of "lossy" digital compression, such as
> > the MPEG upon which DAB and IBOC is based.
>
> Which is a responsibility of the station. They may find it appropriate to
> trade some quality or dynamic range for loudness.
Exactly. I have no problem with processing per se, but these loudness wars
that I've heard about are a thing of the past as far as digital is
concerned.
Aztech
news:a8ekff$636$2...@hammerfield.cambridge.redhat.com...
>
> >> > ... because they can only fit the same signal and maybe a
> >> > small data channel in the bandwidth of the analogue service. ...
> >> Euh. I am sorry, but I'm not very familiar with the US frequency-plan.
> >>
> >> What exactly is the bandwidth of a FM station on the US? And, if there
> >> is some place left for their digital system, why isn't it used nowdays.
> >> It looks a bit daft to have (say) 200 Khz of bandwidth for your signal
> >> and don't use it completely.
>
> > It looks better than I thought, see the following paper:
>
> > http://www.nab.org/SciTech/Dab/Appendixb.pdf
>
> > 96kbps, using AAC! Better audio quality than 192kbps DAB.
>
> Last time I heard, the real IBOC rollout will use a version of
> Lucent's PAC coder instead of AAC. AAC was used for the trials.
> I may have been told wrongly, though: correction invited.
Wasn't there a couple of competing IBOC companies? 'US Digital Radio' went with
AAC and LDR (Lucent Digital Radio?) when with PAC for obvious reasons, then LDR
merged with the competitor and I guess PAC was finally chosen?
Az.
Aztech
news:3CAA8F98...@ix.netcom.com...
> With digital TV out, in standard definition mode, there's enough
> digital bandwidth to broadcast several audio programs within
> the DTV channel. It's already in the specs of DTV to send
> unrelated to TV data streams, i.e., digitized audio (radio).
> Basically, it would just be an extension of the soundtrack
> of the video. Just have more digital "soundtracks" without
> video. Realize that analog TV sound is nearly equivalent
> to an FM radio station. There's slight differences in the
> technical specs, but anyone who lives in a city with a channel
> 6 knows you can hear the sound on an FM radio just below
> 88MHz.
Hrm... but 8VSB isn't even resistant to multipath in a fixed environment, how do
you expect to perform in a mobile environment?
Az.
David Eduardo
"Steve" <info@remove_this.digitalradiotech.co.uk> wrote in message
news:a8f2pm$503$1...@newsg1.svr.pol.co.uk...
> "David Eduardo" <radio...@yahoo.com> wrote in message
> news:9kwq8.6174$l32.392...@newssvr21.news.prodigy.com...
>
> and
> > also done the bus rides at other demonstrations. My opinion, based on
> being
> > a programmer and formerly an engineer is that the digital audio stream
can
> > sound better than analog. All depends on how it is delivered to the
> > transmitter and processed.
>
> How high were the processing levels during this test? I would imagine that
> being a test they would have left the Optimod processors off it.
I was told (keyword "told") that the processing was "recommeded processing
to keep overshoot in control" or some such words. In other words, mild
processing to avoid digital clipping.
>
> > Some of the finest sounding stations, including classical music ones,
have
> > Optimods. Actually, about every significant FM on the planet has one
> (except
> > for the few still using the Ford Taurus processor [anyone who has seen
one
> > knows what I mean]). I just had 3 LA stations and two Phoenix ones put
new
> > 8400s on the air, and they are magnificent!
>
> He did say "ear-bleeding". Now I agree that you shouldn't blame Bob Orban
> for the way his customers use his products but believe me that what
> processing has gone on in the past on FM will not carry through to
digital.
> Take BBC Radio 1 in the UK. It is highly processed on FM but they have
> lowered the processing levels because they were clashing with the MPEG
> encoder. Processors lead to some frequency components becoming unmasked in
> comparison with the original so you have a fundamental trade-off:
>
> Processing level against audio quality
>
> In future you won't be hearing ear-bleeding processing because I've
> witnessed it and for all the arguments about people not caring about audio
> quality, they will not listen to audio quality that is so bad that it is
> unlistenable.
True. And I think statins are generally smart enough to realize that
excessive processing of the digital audio is not in their best interests. We
will probably see a very different Optimod (I'll bet Bob Orban is developing
such a product) for this enhancement.
Funny, no one has asked whether stations will be willing to pay the up-to
$70 thousand dollar annual fee to have the priviledge of making money for
Ibiquity!
>
> I agree. But the processing levels will fall when digital properly takes
> over. The *only* way to keep processing levels high would be to redesign
the
> MPEG encoder to specifically cater for processed audio.
Or, to used different processing models. Which is what I anticipate.
> > Which is a responsibility of the station. They may find it appropriate
to
> > trade some quality or dynamic range for loudness.
>
> Exactly. I have no problem with processing per se, but these loudness wars
> that I've heard about are a thing of the past as far as digital is
> concerned.
Now, there are loudness wars in some parts of the US, but nothing like it
was in the 70's and 80's. Stations in general sound better and the latest
generation of processors allows this with far fewer artifacts; the square
waves are pretty much gone.
Steve
"David Eduardo" <radio...@yahoo.com> wrote in message
news:v5Fq8.6455$co.4082547842@newssvr21.news.prodigy.com...
>
> "Steve" <info@remove_this.digitalradiotech.co.uk> wrote in message
> news:a8f2pm$503$1...@newsg1.svr.pol.co.uk...
> > How high were the processing levels during this test? I would imagine
that
> > being a test they would have left the Optimod processors off it.
>
> I was told (keyword "told") that the processing was "recommeded processing
> to keep overshoot in control" or some such words. In other words, mild
> processing to avoid digital clipping.
Well that's the acceptable way of doing it unlike the way it is being done
on DAB in the UK on some stations.
> > He did say "ear-bleeding". Now I agree that you shouldn't blame Bob
Orban
> > for the way his customers use his products but believe me that what
> > processing has gone on in the past on FM will not carry through to
> digital.
> > Take BBC Radio 1 in the UK. It is highly processed on FM but they have
> > lowered the processing levels because they were clashing with the MPEG
> > encoder. Processors lead to some frequency components becoming unmasked
in
> > comparison with the original so you have a fundamental trade-off:
> >
> > Processing level against audio quality
> >
> > In future you won't be hearing ear-bleeding processing because I've
> > witnessed it and for all the arguments about people not caring about
audio
> > quality, they will not listen to audio quality that is so bad that it is
> > unlistenable.
>
> True. And I think statins are generally smart enough to realize that
> excessive processing of the digital audio is not in their best interests.
We
> will probably see a very different Optimod (I'll bet Bob Orban is
developing
> such a product) for this enhancement.
He's already got one, the Optimod 6200 DAB Audio Processor.
I was was under the impression that people like BBC Radio 1 were using an FM
processor but they're not, they're already using a DAB processor. They
reduced the bit rates and probably left the processing levels unchanged
after reducing the bit rate and it sounded awful. They've reduced them
since. Most other stations have not changed and in time when DAB catches on
they will lose listeners and that's their own fault for not paying enough
attention to audio quality.
The point about multi-band compression being mixed with low bit rate links
is a fundamental trade-off between loudness and audio quality. There is no
getting away from that because MPEG encoders want there to be few large
amplitude frequency components so that the signal can be encoded easily but
multi-band compression attempts to boost all or most of the frequency
components. At high bit rates this isn't a problem because there are enough
bits to encode the signal properly. For example, before Radio 1's bit rate
was reduced they had a pretty high processing level but sounded okay. It is
just at low bit rates that this problem occurs but the way that UK
broadcasting seems to be going to is to cram as many stations into the
bandwidth so you can only assume that they will mainly transmit at the lower
bit rates.
Personally I think that when we're all on digital that people will naturally
move away from the high processing sound towards a lower one anyway.
> Funny, no one has asked whether stations will be willing to pay the up-to
> $70 thousand dollar annual fee to have the priviledge of making money for
> Ibiquity!
That is pretty steep.
> > Exactly. I have no problem with processing per se, but these loudness
wars
> > that I've heard about are a thing of the past as far as digital is
> > concerned.
>
> Now, there are loudness wars in some parts of the US, but nothing like it
> was in the 70's and 80's. Stations in general sound better and the latest
> generation of processors allows this with far fewer artifacts; the square
> waves are pretty much gone.
Thankfully I don't know too much about these wars, and don't really want to
know. ;)
Aztech
<snip>
> True. And I think statins are generally smart enough to realize that
> excessive processing of the digital audio is not in their best interests. We
> will probably see a very different Optimod (I'll bet Bob Orban is developing
> such a product) for this enhancement.
>
> Funny, no one has asked whether stations will be willing to pay the up-to
> $70 thousand dollar annual fee to have the priviledge of making money for
> Ibiquity!
Ouch... I think everyone else had the prudence to go with an open system, with
MP2, yay ;)
Az.
R J Carpenter
> I was was under the impression that people like BBC Radio 1 were using an FM
> processor but they're not, they're already using a DAB processor. They
> reduced the bit rates and probably left the processing levels unchanged
> after reducing the bit rate and it sounded awful. They've reduced them
> since. Most other stations have not changed and in time when DAB catches on
> they will lose listeners and that's their own fault for not paying enough
> attention to audio quality.
Back last November when I got my XM radio I thought that the BBC World
Service sounded pretty ragged. I hadn't listened to it much until last
weekend for the features on the Queen Mother's passing. IMO the sound
of the BBC World Service on XM has greatly improved. As I understand it,
XM uses a lower bit rate for the talk channels such as the BBC.
I understand that XM has an Orban on each of its 100 program services,
and the initial policy (for the music channels) was very little
processing. One "Ink Spots" selection on XM 4 has a lot of "SSssses"
and gave a bit of a problem early on. I think that has also been
considerably improved on a recent hearing. That's about the only
musical selection upon which I have heard really noticable problems on
XM.
Robert Casey
Aztech wrote:
>
>
> Hrm... but 8VSB isn't even resistant to multipath in a fixed environment, how do
> you expect to perform in a mobile environment?
>
>
Good question, don't know.....
Aztech
From the field tests I've seen I don't fancy its chances, but to be fair it
wasn't designed for mobile reception.
Az.
Nick Jeffery
> Hrm... but 8VSB isn't even resistant to multipath in a fixed environment, how do
> you expect to perform in a mobile environment?
It's at times like this you realise how nice COFDM is, isn't it?
If only our telly system was running 8k carriers instead of 2k... But
with the main content provider on the verge of going bankrupt, it's not
really an issue.
--
Nick Jeffery - Leeds, England Station Manager, Purple FM
http://durham.easytiger.ws/
http://www.purplefm.com/
Telephone 07941 349 444 Durham.St...@dur.ac.uk
Lat: N53:50:19 Long: W1:31:00 Dunelm House, DURHAM, DH1 3AN
Robert Orban
>
>I understand that XM has an Orban on each of its 100 program services,
>and the initial policy (for the music channels) was very little
>processing. One "Ink Spots" selection on XM 4 has a lot of "SSssses"
>and gave a bit of a problem early on. I think that has also been
>considerably improved on a recent hearing. That's about the only
>musical selection upon which I have heard really noticable problems on
>XM.
AFAIK, they have a non-Orban processor on each channel at the moment. Sirius,
OTOH, is using Orban 6200s.
Kevin T.
Please tell me where I ever "bashed" Mr. Orban. I simply pointed out
the kinds of problems IBOC causes on the FM and AM bands, and like many
others in the alt.radio.digital newsgroup, I also pointed out how the
use of a large amount of audio processing (as typically provided by
Orban's products) clashes with the lossy digital compression of DAB and
IBOC, resulting in an audio output at the receiver that comes out
sounding worse than it would on regular analog radio with the equivalent
amount and type of audio processing at the transmitter.
Unlike you and some others, I do not consider Mr. Orban to be the God of
the audio processor industry, and if you consider that to be "bashing"
him, then that clearly illustrates your distorted sense of priorities
and beliefs. Mr. Orban may be the Bill Gates of the audio processor
industry, but that does not mean we all have to use, love, and cherish
his products, no more than all of us use, love, and cherish Microsoft
products. And just as plenty of people get along with their computing
activities just fine without ever touching a Microsoft product, there
are plenty of radio stations which do not use Orban processing and get
along just fine.
Kevin Tekel
Owner/operator, KJFE 1500 AM STEREO
with PDSoft "StayMax" audio processing (variable 100%-700% inverse-
reference digital real-time matrix-controlled dynamics processing)
Kevin T.
5 to 9 seconds, to be exact.
XM Satellite Radio has an annoying 2 or 3 second pause when you change
channels before the audio synchs up and fades in. This pretty much
eliminates the hobby of channel surfing.... which is a necessity with
100 channels on a radio that only has 5 presets!!
Dave
http://www.telos-systems.com/news/reprints/pdf/012br32.pdf
Kevin T.
Clear Channel-owned KABL 960 AM STEREO in Oakland, CA is one of the finest
sounding and best programmed radio stations I have ever listened to.
Listen to 960 KABL in AM STEREO on your computer:
http://musicandvideo.myftpsite.net/amstereo/files/stations/North-America/USA/California/ClearChannel-OwnedKABL.mp3
http://musicandvideo.myftpsite.net/amstereo/files/stations/North-America/USA/California/ClearChannel-OwnedKABL2.mp3
Recorded in August 2000 on a Sony SRF-A100 radio in Wide Bandwidth AMAX
AM Stereo mode.
Clear Channel rules!!! ......some of the time...
Kevin T.
And this must be why XM is losing $250,000,000 a year, and Sirius has a
bright sunny future, right?
Steve
> Steve wrote:
>
> > I was was under the impression that people like BBC Radio 1 were using
an FM
> > processor but they're not, they're already using a DAB processor. They
> > reduced the bit rates and probably left the processing levels unchanged
> > after reducing the bit rate and it sounded awful. They've reduced them
> > since. Most other stations have not changed and in time when DAB catches
on
> > they will lose listeners and that's their own fault for not paying
enough
> > attention to audio quality.
>
> Back last November when I got my XM radio I thought that the BBC World
> Service sounded pretty ragged. I hadn't listened to it much until last
> weekend for the features on the Queen Mother's passing. IMO the sound
> of the BBC World Service on XM has greatly improved. As I understand it,
> XM uses a lower bit rate for the talk channels such as the BBC.
XM uses AAC doesn't it? Far far better than MP2 on DAB.
> I understand that XM has an Orban on each of its 100 program services,
> and the initial policy (for the music channels) was very little
> processing. One "Ink Spots" selection on XM 4 has a lot of "SSssses"
> and gave a bit of a problem early on. I think that has also been
> considerably improved on a recent hearing. That's about the only
> musical selection upon which I have heard really noticable problems on
> XM.
It all depends on how high the processing levels are, not if it is applied
or not. Up to a point it is fine. But go past that point and you start
seriously degrading the audio quality.
Steve
news:3cabb12c...@news-server.socal.rr.com...
> XM uses Omnia, do they not?
What bit rate is used for music on XM and Sirius? Am I right in saying they
use AAC?
David Eduardo
> >> Your insistence in bashing Bob Orban was the final clue. <<
>
> Please tell me where I ever "bashed" Mr. Orban.
When you said, "Opti-mud" I got my first clue.
> Unlike you and some others, I do not consider Mr. Orban to be the God of
> the audio processor industry, and if you consider that to be "bashing"
> him, then that clearly illustrates your distorted sense of priorities
> and beliefs. Mr. Orban may be the Bill Gates of the audio processor
> industry, but that does not mean we all have to use, love, and cherish
> his products, no more than all of us use, love, and cherish Microsoft
> products. And just as plenty of people get along with their computing
> activities just fine without ever touching a Microsoft product, there
> are plenty of radio stations which do not use Orban processing and get
> along just fine.
What a non-sequitur. And a good ad hominem, too. The fact is taht radio
stations form Fairbanks to Ushuaia and from Djakarta to J'burg are using the
Optimod in numbers far above those of other products because the box is so
versitiele, you can get the exact sould you want with a bit of sense, a good
ear and patience.
If Bob is not a god, perhaps he is the idol or champion of all of us who
have moved form the Level Devil to the Volumax/Audimax to the LA3-A and the
Audio Prism and the CRL mashers. The good he has done for engineering is
unrivaled.
>
> Kevin Tekel
> Owner/operator, KJFE 1500 AM STEREO
> with PDSoft "StayMax" audio processing (variable 100%-700% inverse-
> reference digital real-time matrix-controlled dynamics processing)
Yeah, right.
David Eduardo
>
Yes. Rather impressive to se about 100 of them in a bunch of racks.
David Eduardo
No, XM is ahead of projections.
It was supposed to lose $250 million last year; they had not, in case you
did not notice, started selling subscriptions but had to build 100 studios,
hire hundreds of staffers, launch two satellites, etc.
Sirius is the late comer and has essentially no subscribers yet.
R J Carpenter
Pardon me for assigning blame that wasn't due. Sorry.
Aztech
> "Dave" <ric...@knac.com> wrote in message
> news:3cabb12c...@news-server.socal.rr.com...
> > XM uses Omnia, do they not?
>
> What bit rate is used for music on XM and Sirius? Am I right in saying they
> use AAC?
PAC - http://www.lucent.com/press/0100/000106.coa.html
Mornin,
Az.
Kevin T.
Show me where I ever intentionally called it "Optimud". That is not
even that good of a put-down! Sounds like something the other
non-Orban-fans in alt.radio.digital made up.
>> Yeah, right. <<
You can download the program at http://mpxplay.tripod.com if you doubt
my description of it.
* Variable 100%-700% = you can select the amount of processing desired,
100% being unprocessed
* Inverse-reference = the baseline reference of the audio level is
raised depending on the % processing level selected (700% being 7 times
normal volume), so that all processing works downward from this level,
rather than typical audio processing which words upward from the
standard reference level
* digital = self-explanatory
* real-time = instantaneous attack time because the audio processing is
performed actively along with the decoding of the digitally stored audio
waveforms, rather than passively against an external audio input
* matrix-controlled = selectable 10% to 500% L-R component level which
performs matrix audio processing for maximum Stereo separation (similar
to the matrix processing used by conventional AM Stereo audio
processing, as opposed to the discrete processing used by FM Stereo
which tends to reduce Stereo separation)
* dynamics processing = self-explanatory
And did I mention this program runs in DOS, on as little as a 486? It
is even being updated to support multichannel digital surround sound
with separate processing for each channel (or combinations of
channels). It already supports Dolby AC3 but is currently limited to
2-channel output.
Kevin T.
Whenever I listen to XM demos in stores, it always comes out sounding
completely monaural, despite claims that it is "stereo". And notice
that
XM is never promoted as being "stereo", or even true digital for that
matter. It is always described as "digital-quality sound", which
implies a quality level less than that of true unmanipulated digital
audio (similar to "leather-quality" vinyl upholstery in automobiles).
Nick Jeffery
> with PDSoft "StayMax" audio processing (variable 100%-700% inverse-
> reference digital real-time matrix-controlled dynamics processing)
"PDSoft" - is that software based, then?
I've got a freebie 4-band software dynamics processor that I often have
a play around with. Seems alright, actually.
Admittedly, it's not an 8400, but it's better than the semi-pro
Behringer stuff we're currently using for peak-limiting and a touch of
compression.
But without a broadcast until October? We've got plenty of time to play
around.
Kevin T.
LOL. I've heard your arguments on this and don't want to belabor the
point. As an XM stockholder, you've probably been hurt enough already.
Nick Jeffery
>>Kevin Tekel
>>Owner/operator, KJFE 1500 AM STEREO
>>with PDSoft "StayMax" audio processing (variable 100%-700% inverse-
>>reference digital real-time matrix-controlled dynamics processing)
>
> Yeah, right.
Do you think he's jealous that he can't afford an Orban box?
What exactly does "inverse-reference digital real-time matrix-controlled
dynamics processing" mean?
I have mentally worked out:
inverse-reference = you couldn't use the output to reference anything
digital = it can be switched either on or off
real-time = you don't have to wait 3 weeks for your audio (useful)
dynamics processing = Explains itself.
The only bit I'm now having difficulty with is "matrix-controlled". Does
it accept orders from Morpheus? :-)
Nick Jeffery
The National Museum of Photography Film And Television lets you see in
to their IMAX projection room. Their 5 floor-to-ceiling racks filled
with audio amplifiers is quite impressive.
I also visited a net hosting utility a year or two back that had racks
and racks of those Cobalt 1U plug and play internet servers. That was
quite funky.
David Eduardo
You are splitting hairs over word interpretation. "Digital quality" is a
marketing term. It means digital. Period.
I have several XM receivers, including one in my office driving a home
theatre sound system. There is very definitely stereo. It is stereo when it
leaves our studios by T1, it is in Stereo when we get it off the satellite
to monitor.
David Eduardo
> >> No, XM is ahead of projections. <<
>
> LOL. I've heard your arguments on this and don't want to belabor the
> point. As an XM stockholder, you've probably been hurt enough already.
Yep. I have been hurt enough to take a partial profit and put the down
payment on a second home in Palm Springs. My profit was just over 400%.
Thanks for asking.
XM is way ahead of projections, and every business pub from the WSJ to
Forbes and Fortune are raving about the technology. Which means that the
buzz will get to Main Street. They now believe they will do over 500
thousand subscriptions this year, which is pretty amazing for a start-up
with totally new technology.
Go anywhere on the web, from Yahoo finance to Edgar to Morningstar to Value
Line and you will see this company profiled as speculative but well ahead of
projections, and you will find that the loss in 2001 was totally expected.
The day it was announced, the stock went up, by the way. The street expected
a bigger loss.
Nick Jeffery
> * matrix-controlled = selectable 10% to 500% L-R component level which
> performs matrix audio processing for maximum Stereo separation (similar
> to the matrix processing used by conventional AM Stereo audio
> processing, as opposed to the discrete processing used by FM Stereo
> which tends to reduce Stereo separation)
Stereo FM (and DAB) radio broadcasters usually, if not always, have some
spatialisation processing involved. It helps improve intellibility for
automotive listening, apparently.
Nick Jeffery
> Whenever I listen to XM demos in stores, it always comes out sounding
> completely monaural, despite claims that it is "stereo". And notice
> that
> XM is never promoted as being "stereo", or even true digital for that
> matter. It is always described as "digital-quality sound", which
> implies a quality level less than that of true unmanipulated digital
> audio (similar to "leather-quality" vinyl upholstery in automobiles).
Being 4,000 miles away, I've not had chance to hear it, or its claims.
"digital-quality sound" is meaningless - I can make, on my computer a
24-bit, 96kHz sampling PCM file. I can also make an 8kHz sampling rate,
4-bit file.
Bot are digital, but vary wildly in quality.
Kevin T.
Apparently you are unfamiliar with the concept of matrix audio
processing. Perhaps Bob himself could explain it, since there are
Optimod audio processors designed for AM Stereo which use this kind of
processing.
Kevin T.
Probably "Intensity Stereo" or somesuch like that, which applies very
heavy lossy digital compression to the L-R component, in order to take
advantage of most people's lack of understand of and appreciation for
the full quality of Stereo sound.
You can hack out most of the L-R component and to most people it still
comes out sounding like "Stereo", but if you listen to the L-R component
by itself (such as through the rear speakers of a matrixed Surround
Sound system), you can clearly hear just how badly its quality is
reduced. In fact Dolby says Pro Logic cannot be reproduced through
Intensity Stereo encoding because the quality loss of the L-R component
is too much.
Kevin T.
This is not the same as true matrix processing. Ordinary "Stereo
enhancement" effects just passively boost the L-R component, which is
not properly controlled and creates too much of a "spacey" and "echoey"
effect. Matrix processing dynamically controls the level of the L-R
component to ensure maximum Stereo separation without causing any
negative effects that occur from boosting the L-R level too much.
AM Stereo uses matrix processing to ensure that monaural listeners do
not experience a loss of loudness during single-channel audio, the
fringe benefit of which is that the Stereo effect is cautiously enhanced
for Stereo listeners, leading to a wider sound-stage without sounding
unnatural.
David Eduardo
"Nick Jeffery" <n.s.j...@durham.ac.uk> wrote in message
news:3CABDB3D...@dur.ac.uk...
> David Eduardo wrote:
> >>Kevin Tekel
> >>Owner/operator, KJFE 1500 AM STEREO
> >>with PDSoft "StayMax" audio processing (variable 100%-700% inverse-
> >>reference digital real-time matrix-controlled dynamics processing)
> >
> > Yeah, right.
>
> Do you think he's jealous that he can't afford an Orban box?
>
> What exactly does "inverse-reference digital real-time matrix-controlled
> dynamics processing" mean?
Supercaifragilisticexpialidocuious?
Nick Jeffery
>>>Stereo FM (and DAB) radio broadcasters usually, if not always, have some spatialisation processing involved. It helps improve intellibility for automotive listening, apparently. <<
>>
Your news client does not appear to be line-wrapping properly.
Hopefully, this will be corrected by Mozilla in my reply.
> AM Stereo uses matrix processing to ensure that monaural listeners do
> not experience a loss of loudness during single-channel audio, the
> fringe benefit of which is that the Stereo effect is cautiously enhanced
> for Stereo listeners, leading to a wider sound-stage without sounding
> unnatural.
Do mono listeners make up most of your audience? Do many people listen
*simply* because you're the only AM stereo station on the dial?
AIUI:
AM stereo systems failed miserably in Europe and the UK. The BBC and IBA
both investigated use of the systems, but they were costly, had no
widely available receivers, and it'd require co-operation with Europe to
rejig the band plan. That wasn't going to happen. :-)
On another note, Kiss 100 London has brilliant station branding. Can't
forget what you're listening to; although I'm listening to "Kiss 229.07
Leeds", technically. And it takes the piss a bit that Bam Bam (Kiss 100)
and Christian O'Connell (Xfm) are on holiday at the same time. :|
Nick Jeffery
> "Nick Jeffery" <n.s.j...@durham.ac.uk> wrote in message
> news:3CABDB3D...@dur.ac.uk...
>
>>dynamics processing" mean?
>
> Supercaifragilisticexpialidocuious?
Yes, mate. But I think you're missing the main point here:
Does it have a wicked bass?
:o)
Nick Jeffery
> XM is way ahead of projections, and every business pub from the WSJ to
> Forbes and Fortune are raving about the technology. Which means that the
> buzz will get to Main Street. They now believe they will do over 500
> thousand subscriptions this year, which is pretty amazing for a start-up
> with totally new technology.
Is XM covering the whole country via the satellite(s), with fill-in
relays only active in a couple of large cities for test purposes?
500,000 takeup isn't bad at all.
In the UK, free-to-air DAB radios have sold 40,000 sets. Even when you
take in to account the population difference, you've effectively sold a
unit to twice as much of the US population as DAB has sold to the
punters over here.
And UK DAB has been on-air since 1998.
Nick Jeffery
> You are splitting hairs over word interpretation. "Digital quality" is a
> marketing term. It means digital. Period.
Digital quality can be pisspoor. I cite BBC Radios 1 and 2 via DAB as a
pair of examples.
> I have several XM receivers, including one in my office driving a home
> theatre sound system. There is very definitely stereo. It is stereo when it
> leaves our studios by T1, it is in Stereo when we get it off the satellite
> to monitor.
I'm not entirely sure of how much you can disclose, but in
alt.radio.digital, we're eager to know which codecs, bitrates, and
stereo model you're using? I suspect it's joint stereo, as is most
digital radio that I've experienced, which leads to muddled and lessened
stereo imaging.
David Eduardo
> >> It is stereo when it leaves our studios by T1, it is in Stereo when we
get it off the satellite to monitor. <<
>
> Probably "Intensity Stereo" or somesuch like that, which applies very
> heavy lossy digital compression to the L-R component, in order to take
> advantage of most people's lack of understand of and appreciation for
> the full quality of Stereo sound.
It's getting pretty obvious that you have memorized or done cut and paste on
some out-of-context facts.
For your information, the audio path at XM, based on the 5 channels I
supervise, is no different than a digital path to a transmitter. Programming
is prepared on full digital mixers (obviously, the mike is not digital...
unless you know of some digital announcers), stored and prepared on a bunch
of Dalet systems and then sent to Washington on a T1 (actually, 5 of them).
At that point, to goes to the XM master control where all the audio sources
are similarly processed and sent to the satellite. It's as digital as you
are going to get given the available bandwidth and existing technology vs.
price ratios.
And it sound damn fine on the receivers we have and in my car. I doubt that
any additional improvements would have any benefit on marketing or user
adoption of the system. You know, Kevin, it's probably appropriate to insert
here something you seem not to know that is highly useful. When in college,
a professor showed me that it took as much time to get to an A- grade as it
did to get form the A- to an A+. Yet both grades were A's, anb both
represented only slight differences in excellence. It can be said for much
in life (including the quality of stereo or digital sound) that the
difference between that A- and the perfect A+ is not worth the effort
because people will not notice the subtle variance. You are being a purist;
the world is usually full of generalists.
Actually, some of the folks here who have over and over tried to get you to
understand the difference between pure technology and the market driven
economy of the US also have some engineering background. And know stereo
when we hear it.
Personally, I put the first stereo FM in South America on the air in the
60's, using equipment, from the turntable preamps to the aluminum antenna
bays was designed and built by me and my staff. That included building the
exciter and stereo generator from parts (not modules) as well as some of the
monitoring gear as well. I believe that and a number of other
accomplishments gives me some right to speak without your constant retort of
"broadcaster have no clue" which you regurgitate incessantly in various and
ugly ways.
The average environment for radio listening is not designed for good
acoustics. From the automobile (now there is a noise-free acoustically
designed chamber!) to an office cubicle to the average sound optimized
suburban living room, we have what is really a hostile environment. Radio
stations have to process, they have to make compromises so that people can
hear radio with a perception of clarity. It really does not entirely matter
how faithful what comes out of the speakers is to the original product; what
is important is whether the listener can enjoy and use our product.
>
> You can hack out most of the L-R component and to most people it still
> comes out sounding like "Stereo",
Irrespective of what you think is being done or what can theoretically be
done to the audio, the perception is reality. Radio is a consumer product.
We do what is necessary to create demand and usage. There is no such thing
as a pragmatic purist. Business is pragmatic.
> but if you listen to the L-R component
> by itself (such as through the rear speakers of a matrixed Surround
> Sound system), you can clearly hear just how badly its quality is
> reduced. In fact Dolby says Pro Logic cannot be reproduced through
> Intensity Stereo encoding because the quality loss of the L-R component
> is too much.
So?
David Eduardo
> David Eduardo wrote:
> > "Nick Jeffery" <n.s.j...@durham.ac.uk> wrote in message
> > news:3CABDB3D...@dur.ac.uk...
> >
> >>What exactly does "inverse-reference digital real-time matrix-controlled
> >>dynamics processing" mean?
> >
> > Supercaifragilisticexpialidocuious?
>
> Yes, mate. But I think you're missing the main point here:
>
> Does it have a wicked bass?
Not just wicked... totally bad-ass bass.
Nick Jeffery
>>>The only bit I'm now having difficulty with is "matrix-controlled". Does it accept orders from Morpheus? :-) <<
Your news client is *still* broken.
> Apparently you are unfamiliar with the concept of matrix audio
> processing. Perhaps Bob himself could explain it, since there are
> Optimod audio processors designed for AM Stereo which use this kind of
> processing.
Yes; matrix audio processing isn't something I haven't have cause to
worry about. I did make a throw-away humourous remark (notice the
smiley), but this seems to have been beyond your comprehension.
I'd gladly read an explanation from the likes of Bob, if he doesn't mind.
David Eduardo
> David Eduardo wrote:
> > You are splitting hairs over word interpretation. "Digital quality" is a
> > marketing term. It means digital. Period.
>
> Digital quality can be pisspoor. I cite BBC Radios 1 and 2 via DAB as a
> pair of examples.
>
> > I have several XM receivers, including one in my office driving a home
> > theatre sound system. There is very definitely stereo. It is stereo when
it
> > leaves our studios by T1, it is in Stereo when we get it off the
satellite
> > to monitor.
>
> I'm not entirely sure of how much you can disclose, but in
> alt.radio.digital, we're eager to know which codecs, bitrates, and
> stereo model you're using? I suspect it's joint stereo, as is most
> digital radio that I've experienced, which leads to muddled and lessened
> stereo imaging.
Someone in engineering at XM would have to release the tech data; I believe
there are some white papers on their site or used to be. Up to the master
control point, just looking at the specks of the Dalet system made just
across the channel from you should answer any source-end questions.
David Eduardo
> David Eduardo wrote:
> > XM is way ahead of projections, and every business pub from the WSJ to
> > Forbes and Fortune are raving about the technology. Which means that the
> > buzz will get to Main Street. They now believe they will do over 500
> > thousand subscriptions this year, which is pretty amazing for a start-up
> > with totally new technology.
>
> Is XM covering the whole country via the satellite(s), with fill-in
There is actually a controversy of sorts inthe US regarding the patenting of
technology that would allow the supposedly 1000+ terrestrial repeaters to
originate local programming. The broadcasters' association is in a bit of a
snit over it, claiming that XM and Sirius were not licensed as anything but
a national service.
As to coverage, the ruddy thing covers all the US, with very, very few tiny,
tine holes noted by users so far. There are aobut 75 thousand of them
through Q1 of this year; over a half million by year end are forecast.
Industry analysts think that there will be between 20 and 40 million by 2010
(although we know "forecast" is also a synonym for "guess").
> 500,000 takeup isn't bad at all.
No, not bad. And that is what has pumped the stock up by about 300% at
today's close vs. its pre-launch low.
> In the UK, free-to-air DAB radios have sold 40,000 sets. Even when you
> take in to account the population difference, you've effectively sold a
> unit to twice as much of the US population as DAB has sold to the
> punters over here.
I did not know that. Fascinating. Can you describe a bit your impressions of
the services, the quality and the receivers that are available? Or point me
to a website?
>
> And UK DAB has been on-air since 1998.
That I knew, but I would have guessed at more receivers. Why do you think it
is going so slow?
Kevin T.
That's funny, the world's most powerful AM Stereo radio station (at
300,000 watts non-directional) is located in Paris, France, as "France
Bleu" on 864 kHz, broadcasting in Motorola C-Quam AM Stereo since the
mid-1990s.
Some smaller stations also broadcast in AM Stereo in Europe, including
stations in Ireland, Spain, Italy, and Greece.
Kevin T.
Meanwhile, Sirius Satellite Radio is said to currently have 213
subscribers nationally.
Yes, that's right... two hundred and thirteen subscribers!!
Nick Jeffery
> Someone in engineering at XM would have to release the tech data; I believe
> there are some white papers on their site or used to be. Up to the master
> control point, just looking at the specks of the Dalet system made just
> across the channel from you should answer any source-end questions.
DALET's French, and as such, I would have no interest in using it :)
AIUI, DALET can accept files of many different compression formats and
bitrates - so, ultimately, it would be down to the broadcaster as to
whether they used (for example) 320kbps MP2 or 128kbps MP2.
Kevin T.
theoretically be done to the audio, the perception is reality. <<
Yes, and you must admit that people like yourself and the folks who
misuse Mr. Orban's products have done a very fine job of getting people
to accept a total lack of quality (of both programming and audio
fidelity) as the norm for radio listening these days. Anybody who
expects more than the norm is a freak, right?
No wonder people don't listen to the radio anymore. The music sucks,
the variety sucks, the programming sucks, the audio quality sucks, the
commercials suck, the DJs suck, etc..... so people just download MP3s
from the 'net, burn them onto CD-Rs, and then listen to that all the
time. If they want to hear about new music, they watch MTV or surf the
Web. This is the perfect way to get away from all the radio stations
that sound the same and play the same music over and over again, mixed
with way too many commercials.
But of course you've got your behind covered. You *know* that because
of the "listener be damned" beliefs that most radio stations share with
you, radio is going downhill fast. So that is why you are involved with
XM, which you hope will be the "replacement" for radio. Even Clear
Channel is heavy into XM because they know their thousands of radio
stations are not going to last if the current trend continues.
Thus I am surprised that you are even supporting IBOC. Why even try to
improve the quality of something that people have come to accept
horrible quality as the norm? If they don't know any better, then
what's the point? What's the point of spending $100,000+ to upgrade a
station to IBOC when 0% of the listeners will be able to receive it, and
even if they could, most people would not be able to tell any difference
in quality anyway?
Kevin Tekel
KJFE 1500 AM STEREO
"Real People, Real Music, Real Radio"
Nick Jeffery
>>>AM stereo systems failed miserably in Europe and the UK. <<
>
> That's funny, the world's most powerful AM Stereo radio station (at
> 300,000 watts non-directional) is located in Paris, France, as "France
> Bleu" on 864 kHz, broadcasting in Motorola C-Quam AM Stereo since the
> mid-1990s.
I should've known about that one - got some samples of it on my hard
drive! I wasn't overly impressed with what I heard - maybe I'm too used
to the nice clean sound of FM and DAB these days!
> Some smaller stations also broadcast in AM Stereo in Europe, including
> stations in Ireland, Spain, Italy, and Greece.
Just the UK, then. The IBA and BBC did do tests, and it was decided it
wasn't worth it.
I think that AM is brilliant for serving voice only services; I find AM
very inteligible with the human voice. As anything else, stereo or not,
I don't really think it cuts it.
Does the C-Quam system still suffer from the night time fading, and will
it cope with the addition of DRM to the band?
Nick Jeffery
> "Nick Jeffery" <n.s.j...@durham.ac.uk> wrote in message
> news:3CABEB8F...@dur.ac.uk...
>
>>take in to account the population difference, you've effectively sold a
>>unit to twice as much of the US population as DAB has sold to the
>>punters over here.
>
> I did not know that. Fascinating. Can you describe a bit your impressions of
> the services, the quality and the receivers that are available? Or point me
> to a website?
The service is below what I'd expect for the amount the receive cost me.
When I purchased it last summer, our state broadcaster the BBC, were
transmitting their services at 192kbps discrete stereo MP2. They've now
shed many of their bitrates - the most popular station is broadcast in
mono for 8 hours in every 24, and the three most popular stations
operate at 128kbps joint stereo.
Commercial stations are typically operating between 128kbps and 160kbps,
the latter sounding more acceptable.
I am still reasonably happy with my purchase - when I'm at University, I
can get good quality reception on the bit of wire that came in the box.
Something that would be impossible with FM in the same situation. It
also gives me a lot more choice - I can listen to the local CHR station,
or one from the next city down, without degrading quality.
It also means that those stations that were previously only available on
AM are represented with a good sound quality. Two of these which I
listen to regularly are talkSPORT and Virgin Radio.
Lastly, there are two stations that are local to London (Xfm playing new
rock music, and Kiss playing dance) and these are available in many
other big cities on local DAB multiplexes. I listen to Xfm a lot, as it
caters for my musical tastes.
Some broadcasters are using the same processing for FM and DAB, some are
using separate DAB processing, some are taking a clean desk feed - all
with varying levels of success.
Many DAB programmes are transmitted over digital satellite (usually
Astra 2) at higher bitrates. Receiver equipment is much cheaper to
acquire, and around 5 million of these are in use - but largely for
Murdoch's "Sky Digital" TV system. How many people use them for radio
reception, I don't know. Note that this type of satellite system is only
suitable for stationary, installed, situations. It can't be used
portably like XM.
>>And UK DAB has been on-air since 1998.
>
> That I knew, but I would have guessed at more receivers. Why do you think it
> is going so slow?
The cheapest standalone receiver to add to a hifi is 300UKP, which is
around 450USD. An automobile outfit costs around the same amount, but
choice is incredibly limited.
Psion (the PDA people) made a USB device to be used in conjunction with
PCs - this too was on sale at 300UKP, but was being sold off for 50UKP.
I have a 300 quid separates tuner and I picked up a Wavefider for 50UKP.
I used the standalone for listening, and the Wavefinder is soley used
for recording/timeshifted listening - it can record the native MP2
stream to hard drive, which I can then later burn to CD as MP2 or MP3
for playback on my DVD player.
I think when the BBC gets its full array of new services online, people
will be more impressed by the content than the audio quality. But the
deciding factor is going to be receiver cost. And people aren't going to
shell out a typical week's wages to get one.
If you would like me to upload a few short off-air samples for you, let
me know.
And now some URLs:
http://www.bbc.co.uk/digitalradio - State Broadcaster Propaganda
http://www.digital1.co.uk/ - National commercial mux operator
http://www.digitalradiotech.co.uk/ - Steve's cynical look at DAB
HTH, HAND.
Nick.
Dave
fact, after a few hours with XM, it's very painful to listen to FM
Stereo. It sounds like it's about to "break up", all the time.
On Wed, 03 Apr 2002 23:08:37 -0500, "Kevin T." <kevtr...@yahoo.com>
wrote:
>>> Yes. Rather impressive to se about 100 of them in a bunch of racks. <<
>
Dave
On Thu, 04 Apr 2002 00:33:53 -0500, "Kevin T." <kevtr...@yahoo.com>
wrote:
>>> It is stereo when it leaves our studios by T1, it is in Stereo when we get it off the satellite to monitor. <<
Steve
"Aztech" <a...@tech.com> wrote in message
news:9gQq8.3596$ee5.23...@news-text.cableinet.net...
>
> "Steve" <info@remove_this.digitalradiotech.co.uk> wrote in message
> news:a8ggm0$d73$1...@news5.svr.pol.co.uk...
> > "Dave" <ric...@knac.com> wrote in message
> > news:3cabb12c...@news-server.socal.rr.com...
> > > XM uses Omnia, do they not?
> >
> > What bit rate is used for music on XM and Sirius? Am I right in saying
they
> > use AAC?
>
> PAC - http://www.lucent.com/press/0100/000106.coa.html
Thanks.
> Mornin,
Was that a late night or an early morning?
Steve
a...@redhat.invalid
>>> It is stereo when it leaves our studios by T1, it is in Stereo when we get it off the satellite to monitor. <<
> Probably "Intensity Stereo" or somesuch like that, which applies very
> heavy lossy digital compression to the L-R component, in order to take
> advantage of most people's lack of understand of and appreciation for
> the full quality of Stereo sound.
> You can hack out most of the L-R component and to most people it still
> comes out sounding like "Stereo", but if you listen to the L-R component
> by itself (such as through the rear speakers of a matrixed Surround
> Sound system),
Okay, but why would anyone do such a weird thing?
> you can clearly hear just how badly its quality is reduced. In fact
> Dolby says Pro Logic cannot be reproduced through Intensity Stereo
> encoding because the quality loss of the L-R component is too much.
Sure, Dolby Surround isn't compatible. Joint Stereo seems like a good
deal to me, though: for a given bit rate, the overall sound quality is
better because less capacity is used to encode identical L and R
signals. Sure, discrete stereo at a high bit rate would be better.
Andrew.
David Eduardo
> >> AM stereo systems failed miserably in Europe and the UK. <<
>
> That's funny, the world's most powerful AM Stereo radio station (at
> 300,000 watts non-directional) is located in Paris, France, as "France
> Bleu" on 864 kHz, broadcasting in Motorola C-Quam AM Stereo since the
> mid-1990s.
Actually, 300,000 watts in Europe is not particularly high power.
David Eduardo
They launched literally a few days ago.
Aztech
> Kevin T. wrote:
> >>>AM stereo systems failed miserably in Europe and the UK. <<
> >
> > That's funny, the world's most powerful AM Stereo radio station (at
> > 300,000 watts non-directional) is located in Paris, France, as "France
> > Bleu" on 864 kHz, broadcasting in Motorola C-Quam AM Stereo since the
> > mid-1990s.
>
> I should've known about that one - got some samples of it on my hard
> drive! I wasn't overly impressed with what I heard - maybe I'm too used
> to the nice clean sound of FM and DAB these days!
Of course nearly all the AM transmitters in Europe do actually support AM
stereo, they could enable it by just flicking a switch if they had approval.
Isn't AM still pretty popular in France? AM seems to be pretty much dead in the
UK, what do we have... BBC 5Live and TalkSport on MW, R4-FM relay on LW, and no
domestic stuff on SW?
Roll on DRM.
Az.
Aztech
news:qJ_q8.783$Tp4.10...@newssvr21.news.prodigy.com...
Not in France... they seem to broadcast everything at high power! It doesn't
exactly placate her neighbours ;)
Az.
R J Carpenter
While XM is doing quite well, being firstest isn't always the route to
success. I like the content of XM, but that doesn't mean they will
ultimately prevail.
Think of the Comet jet airliner - years ahead of the others and a very
painful learning experience.
OK. Avro in Canada would have been first with a passenger jet by a yet
wider margin, but funding was cut off after the prototype flew.
Aztech
<snip>
> Was that a late night or an early morning?
Early... got woken up by a couple of foxes fighting on my lawn. I can see why
they want to ban hunting, they seem quite capable of killing each other without
our help ;)
They can 'arf bloody howl.
Az.
Aztech
> Kevin T. wrote:
> > Whenever I listen to XM demos in stores, it always comes out sounding
> > completely monaural, despite claims that it is "stereo". And notice
> > that
> > XM is never promoted as being "stereo", or even true digital for that
> > matter. It is always described as "digital-quality sound", which
> > implies a quality level less than that of true unmanipulated digital
> > audio (similar to "leather-quality" vinyl upholstery in automobiles).
>
>
> "digital-quality sound" is meaningless - I can make, on my computer a
> 24-bit, 96kHz sampling PCM file. I can also make an 8kHz sampling rate,
> 4-bit file.
>
> Bot are digital, but vary wildly in quality.
DAB is now promoted as having "crystal clear digital sound", they seem to do a
fair bit of promotion on Classic FM, I guess they believe demographic is loaded.
Az.
David Eduardo
> >> Irrespective of what you think is being done or what can
> theoretically be done to the audio, the perception is reality. <<
>
> Yes, and you must admit that people like yourself and the folks who
> misuse Mr. Orban's products have done a very fine job of getting people
> to accept a total lack of quality (of both programming and audio
> fidelity) as the norm for radio listening these days. Anybody who
> expects more than the norm is a freak, right?
Actually, the quality of audio in most major markets has improved in the
last decade or so due to better processing with fewer artifacts and the
reealization of most programmers that high compression is fatiguing and bad
for TSL.
>
> No wonder people don't listen to the radio anymore.
Actually, Americans listen to as many weekly hours of radio todya as they
did in pre-TV frezee 1951. This was before TV, before cable, before
satellite TV, before the Interned, before video games, before extended work
hours. 21 hours then, 21 hours then.
> The music sucks,
> the variety sucks, the programming sucks, the audio quality sucks, the
> commercials suck, the DJs suck, etc..... so people just download MP3s
> from the 'net, burn them onto CD-Rs, and then listen to that all the
> time.
Your opinion. Your right. But not exactly what the 95% of Americans who
listen wekly to radio believe.
And as to MP3's, you are much exaggerating. In certain ages and
socioeconomic levels, this may be partly true. But most people don't have
the equipment, the time and the need to do this. In fact, I have actually
done series of random calls form a database and been able to go for hundreds
of aanswers without finding anyone who made MP3 CDs or did MP3 downloads.
Kevin, quit aapplying your tastes and standards to the entire US of A.
> If they want to hear about new music, they watch MTV or surf the
> Web.
This is becasue most people don't actively want to hear new music.
> This is the perfect way to get away from all the radio stations
> that sound the same and play the same music over and over again, mixed
> with way too many commercials.
Radio has fewer commercials today than it did in the 50's and 60's in the
so-called glory days of Top 40 music radio.
>
> But of course you've got your behind covered. You *know* that because
> of the "listener be damned" beliefs that most radio stations share with
> you, radio is going downhill fast.
I have no evidence of this. Do't think for me. You have a hard enough time
doing that on your own behalf. You have no idea what I think or know.
> So that is why you are involved with
> XM, which you hope will be the "replacement" for radio.
No, I think it is a supplement for the erson who previously used cassettes,
CDs or MP3s in the car. The more passionate music purists or those who can't
find a more niche format locally will love XM and Sirius. It is part of the
total entertainment mix.
> Even Clear
> Channel is heavy into XM because they know their thousands of radio
> stations are not going to last if the current trend continues.
Clear Channel, with less than 4% of the XM stock, is not "heavily" into XM.
> Thus I am surprised that you are even supporting IBOC.
I don't support IBOC. I believe it has potential and it has a low cost of
entry for a high possible gain.
> Why even try to
> improve the quality of something that people have come to accept
> horrible quality as the norm?
As Mr. Maus has said, you ignore market forces. The receiver manufactures
will back a digital radio solution as it puts into play the replacement of
700 million radios in the US... that is why, in the end, VHS won and why CDs
won.
> If they don't know any better, then
> what's the point? What's the point of spending $100,000+ to upgrade a
> station to IBOC when 0% of the listeners will be able to receive it, and
> even if they could, most people would not be able to tell any difference
> in quality anyway?
The point? Radio is a business. If there is profit potential, we will see
it. If not, like AM stereo,it will die.
Aztech
> David Eduardo wrote:
> > XM is way ahead of projections, and every business pub from the WSJ to
> > Forbes and Fortune are raving about the technology. Which means that the
> > buzz will get to Main Street. They now believe they will do over 500
> > thousand subscriptions this year, which is pretty amazing for a start-up
> > with totally new technology.
>
> Is XM covering the whole country via the satellite(s), with fill-in
> relays only active in a couple of large cities for test purposes?
>
> 500,000 takeup isn't bad at all.
Indeed... the FM services in the US must be bloody awful ;)
Az.
Aztech
> David Eduardo wrote:
> > "Dave" <ric...@knac.com> wrote in message
> > news:3cabb12c...@news-server.socal.rr.com...
> >
> >>XM uses Omnia, do they not?
> >
>
> to their IMAX projection room. Their 5 floor-to-ceiling racks filled
> with audio amplifiers is quite impressive.
>
> I also visited a net hosting utility a year or two back that had racks
> and racks of those Cobalt 1U plug and play internet servers. That was
> quite funky.
Yup, until you realise those Cobalt servers are just AMD K6-2's, then it's funny
;)
Az.
Cooperstown.Net
> > >> 500,000 takeup isn't bad at all. <<
> >
> > Meanwhile, Sirius Satellite Radio is said to currently have 213
> > subscribers nationally.
> >
> > Yes, that's right... two hundred and thirteen subscribers!!
>
> They launched literally a few days ago.
Your instinct to be gracious and diplomatic is admirable, but analysis is
about dealing with what is. Sirius launched in four cities seven weeks ago
today.
Jerome
Aztech
news:St%q8.19920$GF1.3...@typhoon.nyroc.rr.com...
That's incidental... the real beef is how quickly they will be included in new
cars, remember GM and Ford have investments in each particular broadcaster.
These companies are in it for the long haul, so comments like "x company has
sold y number of tuners in z weeks" isn't really indicative of how the market
will play out.
Az.
Richard Lambley
"Kevin T." <kevtr...@yahoo.com> wrote:
> >> AM stereo systems failed miserably in Europe and the UK. <<
>
> That's funny, the world's most powerful AM Stereo radio station (at
> 300,000 watts non-directional) is located in Paris, France, as "France
> Bleu" on 864 kHz, broadcasting in Motorola C-Quam AM Stereo since the
> mid-1990s.
France Bleue, surely. But if it's been such a success in AM stereo,
why do I never see receivers for it in French shops?
Richard
--
Richard Lambley
Nick Jeffery <n.s.j...@durham.ac.uk> wrote:
> David Eduardo wrote:
> > Someone in engineering at XM would have to release the tech data; I believe
> > there are some white papers on their site or used to be. Up to the master
> > control point, just looking at the specks of the Dalet system made just
> > across the channel from you should answer any source-end questions.
>
> DALET's French, and as such, I would have no interest in using it :)
So is COFDM, isn't it? If you're going to shun anything French, you
will miss out on an awful lot of life's pleasures.
Richard
--
Aztech
news:6b2eeb21...@wireless.globalnet.co.uk...
Well OFDM was a technology from the US military, but the French did the modern
COFDM I believe.
Az.