Dirty Digital [sic.]
John Phillips
"Hi-Fi World"? I picked up a copy for some amusement during a journey
yesterday and was stunned by the article's technical incompetence.
Keywood says of CD that "dynamic range is limited to 85 dB or so by
dither noise" (incorrect - it's actually about 93.3 dB IIRC for 2 LSB p-p
of TPDF dither). Then he complains, disingenuously, about the "dirty
distortion" of quantization on CD (he calls it "digital distortion"),
misunderstanding the fact that it just isn't present when you use dither.
He even misunderstands the issue of correlation between signal and
quantization error, calling them uncorrelated whereas they actually
are correlated and dither's job is to de-correlate the two.
He mixes up distortion and noise inconsistently under the single term
"distortion" sometime meaning noise, sometimes distortion and sometimes
noise+distortion.
Here's another example. He says CD distortion [sic.] is 10% at -80 dB
(dBFS he means, I assume) and later says that "LP is benign and also
produces ten times less distortion than CD at low levels (0.1% to 1%)".
In fact at the comparable low level on LP of -80 dB (WRT 0 dB = 5 cm/s,
I will assume) the LP noise floor is actually above the signal and the
LP's distortion in Keywood's terms is above 100%.
He says of the music business that it "now tries to keep music levels
well above the unacceptably high distortion floor of CD that we illustrate
here". Well, that's a new explanation for the "loudness war".
I think Keywood should have a good look at Jim Lesurf's "Good Resolutions"
article at http://www.audiomisc.co.uk/HFN/goodresolutions/page1.html
(in particular figure 5 on page 2 will show him a realistic comparison
of dynamic range of CD versus LP). Also Jim's article "In a Dither"
at http://www.audiomisc.co.uk/inadither/Page1.html would show him where
his misunderstanding about dither lies.
Keywood starts out with "This isn't a hatchet job of the poor little
silver Frisbee" and then proceeds to try just that. In fact through
his clear technical misunderstandings the only thing that suffers a
"hatchet job" is Keywood's own reputation for competence.
--
John Phillips
Jim Lesurf
<news...@DontUseThis.mainly.me.uk> wrote:
[snip]
> I think Keywood should have a good look at Jim Lesurf's "Good
> Resolutions" article at
> http://www.audiomisc.co.uk/HFN/goodresolutions/page1.html (in particular
> figure 5 on page 2 will show him a realistic comparison of dynamic range
> of CD versus LP). Also Jim's article "In a Dither" at
> http://www.audiomisc.co.uk/inadither/Page1.html would show him where his
> misunderstanding about dither lies.
I also suspect that with many of the old analogue original recordings the
recorded noise level is enough to dither adequately any transfer onto CD-A
- even if the engineers don't explicitly add in dither or noise shaping whe
doing the ADC. :-)
FWIW **many** years ago I contacted him, giving much the same explanation
as on the pages you refer to above - including example spectra - and giving
details of the basic explanations. Prompted by an article he'd published
back then making similar comments to the recent one.
I hoped/assumed at the time that he'd realise he might simply be making a
mistake, and misunderstanding the situation. Point being that what I was
saying wasn't 'new' or my own idea. Just standard information theory,
supported by practice, and evidenced by appropriate methods.
Got no-where.
I'm afraid he regularly makes comments like those in the recent issue of
HFW. I read them and just sighed.
I also tend to take with a pinch of salt some of the THD values they report
for things like CD players. Partly due to the possibility they are using
undithered discs - so reporting the effect of undithered quantisation.
Partly because the values often look to me just like the noise floor you'd
get from dithered FFTs with durations in the range 16k to 64k samples.
If so, the consquence could be that the values they publish may tell you
more about their measurement system and how they 'interpret' the results
than about the CD player being tested.
> Keywood starts out with "This isn't a hatchet job of the poor little
> silver Frisbee" and then proceeds to try just that. In fact through his
> clear technical misunderstandings the only thing that suffers a "hatchet
> job" is Keywood's own reputation for competence.
As I say above, NK has form as long as yer arm on this. :-) From comments
I have heard in private, others have also given up trying to explain some
things to him. To me, this is a shame. He did do some superb work in the
past on topics like the resonances in tone arms, etc, which showed up some
very interesting things. Deserves respect for much of what he did. I also
admire HFW for when they do things like publish kits for amps or speakers
and encourage readers to get involved in building. I was pleased when HFW
started up for these sorts of reasons, and good luck to them. But... I
guess that we all get in a muddle about some things. Only human.
So I doubt he'd read the webpages you reference above [1] or, likely - if
he did - then he simply wouldn't accept what they say.
Slainte,
Jim
[1] Perhaps worth admitting here that the webpages were themselves prompted
by seeing NK make these sorts of assertions in another HFW item a few years
ago. But when producing the webpages I concentrated on the topic and
glossed over where I'd read what I was reacting to. :-)
--
Change 'noise' to 'jcgl' if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scots_Guide/intro/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html
Jim Lesurf
>
> FWIW **many** years ago I contacted him, giving much the same
> explanation as on the pages you refer to above
Just checked, and my copy of the letter is dated 1993. So 25 years ago!
:-)
Slainte,
Jim
Arny Krueger
in message news:slrng5d1ij....@linux.mainly.me.uk
> Has anyone read the article "Dirty Digital" by Noel
> Keywood in July's "Hi-Fi World"? I picked up a copy for
> some amusement during a journey yesterday and was stunned
> by the article's technical incompetence.
This page seems like a potential sounding board for your comments:
http://www.hi-fiworld.co.uk/hfw/email1.html
BTW, your comments seem well-reasoned, and believable, although I haven't
read the article.
Mike Coatham
> On 16 Jun, no...@audiomisc.co.uk wrote:
>> FWIW **many** years ago I contacted him, giving much the same
>> explanation as on the pages you refer to above
>
> Just checked, and my copy of the letter is dated 1993. So 25 years ago!
> :-)
>
> Slainte,
>
> Jim
>
digital terms :).
Chris J Dixon
>Just checked, and my copy of the letter is dated 1993. So 25 years ago!
> :-)
>
15 years or 1983?
Chris
--
Chris J Dixon Nottingham UK
ch...@cdixon.me.uk
Have dancing shoes, will ceilidh.
Jim Lesurf
<coa...@es.co.nz>
wrote:
Oops! Yes, sorry about that. :-)
Jim Lesurf
> >Just checked, and my copy of the letter is dated 1993. So 25 years ago!
> > :-)
> >
> 15 years or 1983?
1993 is correct. The '25' was a 'senior moment'. :-)
John Phillips
> In article <slrng5d1ij....@linux.mainly.me.uk>, John Phillips
><news...@DontUseThis.mainly.me.uk> wrote:
>
> I also suspect that with many of the old analogue original recordings the
> recorded noise level is enough to dither adequately any transfer onto CD-A
> - even if the engineers don't explicitly add in dither or noise shaping whe
> doing the ADC. :-)
I have wondered about that and the CD-A timeline.
IIRC Lipschitz and Vanderkooy were publishing about dither in JAES in
about 1984 and just after. Although dither had been know for a long
time I suspect you are right that noise floors for material transferred
to CD were probably sufficient in the early days of CD (1982-ish)
to render external dither unnecessary.
One of my musings was that for a short period after ADCs got better it
may have been that CDs lacking dither but displaying the effects of
quantization noise might have made it onto the market. I have no idea
if this did actually happen, though.
> As I say above, NK has form as long as yer arm on this. :-) From comments
> I have heard in private, others have also given up trying to explain some
> things to him. ...
Well I guess I won't try.
--
John Phillips
Arny Krueger
in message news:slrng5g1c7....@linux.mainly.me.uk
> On 2008-06-16, Jim Lesurf <no...@audiomisc.co.uk> wrote:
>> In article <slrng5d1ij....@linux.mainly.me.uk>,
>> John Phillips <news...@DontUseThis.mainly.me.uk> wrote:
>>
>> I also suspect that with many of the old analogue
>> original recordings the recorded noise level is enough
>> to dither adequately any transfer onto CD-A - even if
>> the engineers don't explicitly add in dither or noise
>> shaping whe doing the ADC. :-)
>
> I have wondered about that and the CD-A timeline.
>
> IIRC Lipschitz and Vanderkooy were publishing about
> dither in JAES in about 1984 and just after. Although
> dither had been know for a long time I suspect you are
> right that noise floors for material transferred to CD
> were probably sufficient in the early days of CD
> (1982-ish) to render external dither unnecessary.
AFAIK Vanderkooy and Lipshitz were knowingly publishing old news, in an
effort to overcome some pretty strange false claims that were being
circulated at the time by people who should have known better.
> One of my musings was that for a short period after ADCs
> got better it may have been that CDs lacking dither but
> displaying the effects of quantization noise might have
> made it onto the market. I have no idea if this did
> actually happen, though.
The earliest CD players had converters good enough to demonstrate dynamic
range on the order of 93 dB, which is pretty close to the theoretical max:
http://www.pcavtech.com/play-rec/Sony_CDP-101/index.htm#DR_DA
About 15 or more years later, a highly-regarded CD player improved on the
legacy players performance by only about 1 dB
http://www.pcavtech.com/play-rec/cd67se/index.htm#DR_LB
The noise floor of a well-made recording is on the order of 75-80 dB. Below
that is the noise floor, usually from analog (thermal) sources. This is many
times more than is required to properly dither a proper 16 bit conversion.
Dave Plowman (News)
Arny Krueger <ar...@hotpop.com> wrote:
> The noise floor of a well-made recording is on the order of 75-80 dB.
> Below that is the noise floor, usually from analog (thermal) sources.
> This is many times more than is required to properly dither a proper 16
> bit conversion.
Yup. Anything that starts off life at a microphone is unlikely to do very
much better. And most recordings use several microphones...
--
*I'll try being nicer if you'll try being smarter
Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.
Eeyore
Arny Krueger wrote:
> The earliest CD players had converters good enough to demonstrate dynamic
> range on the order of 93 dB, which is pretty close to the theoretical max:
Oh come on !
The earliest CD players were utter SHITE. Esp the CDP-101. Truncated reverb
tails is what I remember especially.
On Pink Floyd it sounded dreadful. I have a special memory of that.
Thankfully the technology has improved awesomely since.
Graham
Eeyore
Arny Krueger wrote:
> The noise floor of a well-made recording is on the order of 75-80 dB.
Have you gone completely MAD ?
I can beat you by easily 50dB.
Graham
Eeyore
"Dave Plowman (News)" wrote:
> Yup. Anything that starts off life at a microphone is unlikely to do very
> much better. And most recordings use several microphones...
Really good microphones have equivalent acoustic noise levels of well below
20 dB.
Graham
Dave Plowman (News)
Eeyore <rabbitsfriend...@hotmail.com> wrote:
> > Yup. Anything that starts off life at a microphone is unlikely to do
> > very much better. And most recordings use several microphones...
> Really good microphones have equivalent acoustic noise levels of well
> below 20 dB.
There's rather more to the average chain than just the microphone.
--
*Ham and Eggs: Just a day's work for a chicken, but a lifetime commitment
Dave Plowman (News)
Eeyore <rabbitsfriend...@hotmail.com> wrote:
> The earliest CD players were utter SHITE. Esp the CDP-101. Truncated
> reverb tails is what I remember especially.
You mean fading out the track early in the CD mastering to try and stop
you hearing the tape hiss?
--
Eeyore
"Dave Plowman (News)" wrote:
> Eeyore wrote:
Someone else (edited out) wrote.
> > > Yup. Anything that starts off life at a microphone is unlikely to do
> > > very much better. And most recordings use several microphones...
>
> > Really good microphones have equivalent acoustic noise levels of well
> > below 20 dB.
>
> There's rather more to the average chain than just the microphone.
Please elaborate with especial regard to where you think my figures are
wrong.
Graham
Eeyore
"Dave Plowman (News)" wrote:
> Eeyore wrote:
> > The earliest CD players were utter SHITE. Esp the CDP-101. Truncated
> > reverb tails is what I remember especially.
>
> You mean fading out the track early in the CD mastering to try and stop
> you hearing the tape hiss?
NO.
I mean failure of signal resolution compared to CD (on a Sony CDP-101) with
vinyl on my Garrard 401 wirh Ortofon RMG309 arm and M75E II cartridge.
And (in my mind) you'd have to be DEAF not to notice it.
Graham
Phil Allison
"Eeysore = total NUT CASE "
>
>> > The earliest CD players were utter SHITE. Esp the CDP-101. Truncated
>> > reverb tails is what I remember especially.
>>
>> You mean fading out the track early in the CD mastering to try and stop
>> you hearing the tape hiss?
>
> NO.
>
> I mean failure of signal resolution compared to CD (on a Sony CDP-101)
> with
> vinyl on my Garrard 401 wirh Ortofon RMG309 arm and M75E II cartridge.
** No turntable will play a CD and no CD player will play an LP.
Get the point - fuckwit ?
> And (in my mind) you'd have to be DEAF not to notice it.
** You have to be brain dead to wildly assume that CDs and LPs derived from
multi-generation tapes and "re-mastered " by god knows who on god know what
can be used to make such comparisons.
Totally invalid test method, used only by the worst sort of audiophool
cretins.
..... Phil
Eeyore
Phil Allison wrote:
> "Eeysore = total NUT CASE "
> >
> >> > The earliest CD players were utter SHITE. Esp the CDP-101. Truncated
> >> > reverb tails is what I remember especially.
> >>
> >> You mean fading out the track early in the CD mastering to try and stop
> >> you hearing the tape hiss?
> >
> > NO.
> >
> > I mean failure of signal resolution compared to CD (on a Sony CDP-101)
> > with
> > vinyl on my Garrard 401 wirh Ortofon RMG309 arm and M75E II cartridge.
>
> ** No turntable will play a CD and no CD player will play an LP.
>
> Get the point - fuckwit ?
Go fuck a pig you MORON.
Phil Allison
> And (in my mind) you'd have to be DEAF not to notice it.
** You have to be brain dead to wildly assume that CDs and LPs derived from
multi-generation tapes and "re-mastered " by god knows who on god know what
can be used to make such comparisons.
Totally invalid test method, used only by the worst sort of audiophool
cretins.
" Go fuck a pig you MORON."
..... Phil
David Looser
news:48599413...@hotmail.com...
Do you do all your recording in an anechoic chamber then?
David.
Jim Lesurf
> news:slrng5g1c7....@linux.mainly.me.uk
> > On 2008-06-16, Jim Lesurf <no...@audiomisc.co.uk> wrote:
> >
> > IIRC Lipschitz and Vanderkooy were publishing about dither in JAES in
> > about 1984 and just after. Although dither had been know for a long
> > time I suspect you are right that noise floors for material
> > transferred to CD were probably sufficient in the early days of CD
> > (1982-ish) to render external dither unnecessary.
> AFAIK Vanderkooy and Lipshitz were knowingly publishing old news, in an
> effort to overcome some pretty strange false claims that were being
> circulated at the time by people who should have known better.
That is also my recollection. I can't remember when the first work on
dither was done, but I think it was produced a long time ago. Hence there
really isn't much excuse for someone writing magazine articles like NKs not
to understand it. I was certainly reading about such matters long ago.
FWIW prompted by the thread I got out the latest HFW and re-read his
article with more care. Can't say I enjoyed the experience, but did so out
of curiosity and a wish to be fair.
The problem seems to be that he systematically misunderstands a set of
related matters. These don't seem to be confined to dither, but also cover
aspects of measurement and how to understand what a spectrum is telling
him.
Maybe I should do some more on this sometime, to cast some light on the
ways people can easily misundestand such matters.
> > One of my musings was that for a short period after ADCs got better it
> > may have been that CDs lacking dither but displaying the effects of
> > quantization noise might have made it onto the market. I have no idea
> > if this did actually happen, though.
> The earliest CD players had converters good enough to demonstrate
> dynamic range on the order of 93 dB, which is pretty close to the
> theoretical max:
> http://www.pcavtech.com/play-rec/Sony_CDP-101/index.htm#DR_DA
I can add that the results you show seem consistent with that reported
by Martin Colloms in 1983. You have a better analyser, though. :-)
> About 15 or more years later, a highly-regarded CD player improved on
> the legacy players performance by only about 1 dB
> http://www.pcavtech.com/play-rec/cd67se/index.htm#DR_LB
> The noise floor of a well-made recording is on the order of 75-80 dB.
> Below that is the noise floor, usually from analog (thermal) sources.
> This is many times more than is required to properly dither a proper 16
> bit conversion.
I'd be interested in seeing data on the noise performance of studio mics
and preamps, etc. If I recall correctly, their bandwidths also may cast
some doubt on the idea that LP recordings provide wide ultrasonic
bandwidths of genuine recorded sounds. (As distinct from distortion
products, etc.)
Slainte,
Jim
Jim Lesurf
> Arny Krueger wrote:
> > The earliest CD players had converters good enough to demonstrate
> > dynamic range on the order of 93 dB, which is pretty close to the
> > theoretical max:
> Oh come on !
> The earliest CD players were utter SHITE. Esp the CDP-101. Truncated
> reverb tails is what I remember especially.
> On Pink Floyd it sounded dreadful. I have a special memory of that.
Prompted by what you say, I had a look at the first review of the CDP101 in
Hi Fi News. (Martin Colloms, March 1983).
This shows measurements of the nominal THD with test signals down to -80
dBFS. The results seem quite typical for a CD player of the time, and would
not look particularly odd nowdays - allowing for the limits of the
measurement kit he had at the time. These signals would probably be well
below the noise level on an LP of the same recording - unless those making
the LP employed extra level compression. Indeed, at -80dBFS they might be
below the noise level on the analogue tapes for DSoTM. The noise from the
tapes might have dithered the results nicely *if* the engineers making the
CD then resisted playing about with the results. :-)
Given this, it seems dubious that what you claim was due to the player
trunkating the reverb. The player MC tested seemed to perform without
trunkating signals well below what you be hearing above noise on an LP.
Reading the article I did note one comment by MC, though. He borrowed some
recordings and CDs from various CD/LP companies. Then commented that the
only ones that systematically had a full dynamic range were the ones from
DECCA. Others were reported as being trunkated to quantisation levels much
poorer than the 16-bit level.
So perhaps you are confusing poor resolution *CDs* with the player being
used. Or perhaps your player was faulty.
But I can't comment personally on the Sony as I've not used one. That
said, I happily used a 1st generation Marantz for about a decade, and found
no signs of 'trunkated reverb tails' being due to the player. Although I
have found that the quality of CDs varies a lot! Makes me wonder if a
number of people in the biz have an understanding of digital audio on a par
with NK. :-)
I have a feeling some later reviews have linearity plots down to below
-95dB. So may see if I can find one for the CDP101 sometime.
> Thankfully the technology has improved awesomely since.
Odd then that HFW seems in recent years to have taken to recommending
people buy some of the old machines like these for their sound quality.
:-)
Slainte,
Jim
Alan White
wrote:
>That is also my recollection. I can't remember when the first work on
>dither was done, but I think it was produced a long time ago. Hence there
>really isn't much excuse for someone writing magazine articles like NKs not
>to understand it. I was certainly reading about such matters long ago.
>...
Dither was certainly used in the BBC thirteen channel PCM coders used
for the BBC radio distribution network in 1972(?)
--
Alan White
Mozilla Firefox and Forte Agent.
Twenty-eight miles NW of Glasgow, overlooking Lochs Long and Goil in Argyll, Scotland.
Webcam and weather:- http://windycroft.gt-britain.co.uk/weather
John Phillips
> In article <48599399...@hotmail.com>, Eeyore
><rabbitsfriend...@hotmail.com> wrote:
>> Arny Krueger wrote:
>> > The earliest CD players had converters good enough to demonstrate
>> > dynamic range on the order of 93 dB, which is pretty close to the
>> > theoretical max:
>
>> Oh come on !
>
>> The earliest CD players were utter SHITE. Esp the CDP-101. Truncated
>> reverb tails is what I remember especially.
>
>> On Pink Floyd it sounded dreadful. I have a special memory of that.
>
> Prompted by what you say, I had a look at the first review of the CDP101 in
> Hi Fi News. (Martin Colloms, March 1983).
> Reading the article I did note one comment by MC, though. He borrowed some
> recordings and CDs from various CD/LP companies. Then commented that the
> only ones that systematically had a full dynamic range were the ones from
> DECCA. Others were reported as being trunkated to quantisation levels much
> poorer than the 16-bit level.
This was also reported in Stereophile's review of the CDP-101 (or one of
the follow-ups). See http://www.stereophile.com/cdplayers/193/index.html
and subsequent pages.
Of the CDP-101 and a Decca CD: "Sonically, the Decca was worth all
the others put together, and -— multimiked recording and tipped-up
top notwithstanding —- delivered the most realistic reproduction of an
orchestra I have heard in my home in 20-odd years of audio listening!"
And, disagreeing with Eeyore: "In fact, on the basis of that Decca disc
alone, I am now fairly confident about giving the Sony player a clean
bill of health, and declaring it the best thing that has happened to
music in the home since The Coming of Stereo."
> So perhaps you are confusing poor resolution *CDs* with the player being
> used. Or perhaps your player was faulty.
In fact on the specific issue of digital processing with or without dither
and the effect on resolution in "reverb tails", since the CDP-101 had
only analogue reconstruction filters there seems to be no possibility
to blame the player - only the CD mastering.
--
John Phillips
Jim Lesurf
> > Prompted by what you say, I had a look at the first review of the
> > CDP101 in Hi Fi News. (Martin Colloms, March 1983). ... [snip] ...
> > Reading the article I did note one comment by MC, though. He borrowed
> > some recordings and CDs from various CD/LP companies. Then commented
> > that the only ones that systematically had a full dynamic range were
> > the ones from DECCA. Others were reported as being trunkated to
> > quantisation levels much poorer than the 16-bit level.
> This was also reported in Stereophile's review of the CDP-101 (or one of
> the follow-ups). See
> http://www.stereophile.com/cdplayers/193/index.html and subsequent
> pages.
I also notice that the Stereophile pages give a reference to an article on
Dither which Martin Colloms had published in the August 1983 issue of HFN.
So it is clear that many people in the consumer audio mags knew about this
when CD was launched. :-)
> > So perhaps you are confusing poor resolution *CDs* with the player
> > being used. Or perhaps your player was faulty.
> In fact on the specific issue of digital processing with or without
> dither and the effect on resolution in "reverb tails", since the CDP-101
> had only analogue reconstruction filters there seems to be no
> possibility to blame the player - only the CD mastering.
You having mentioned that made me check, and I can confirm that the
squarewave results in the HFN review of the CDP101 show no 'pre-ringing'. I
haven't found a detailed spec for the CDP101, and can't recall any details.
But it looks like it used the simple method of 16 bit DACs followed by an
analogue filter. The Philips method of using 14 bit x 4 oversampled
employed transverse digital filters. The symptom for this was the familiar
'time symmetric' ringing before and after each square wave edge.
Above said, what I don't know is how monotonic or linear the Sony DACs
were. But the THD results I've seen don't look particularly bad - allowing
for the kit used and the noise floor of a dithered signal and a finite
duration FFT.
Eeyore
John Phillips wrote:
> Has anyone read the article "Dirty Digital" by Noel Keywood in July's
> "Hi-Fi World"? I picked up a copy for some amusement during a journey
> yesterday and was stunned by the article's technical incompetence.
>
> Keywood says of CD that "dynamic range is limited to 85 dB or so by
> dither noise" (incorrect - it's actually about 93.3 dB IIRC for 2 LSB p-p
> of TPDF dither). Then he complains, disingenuously, about the "dirty
> distortion" of quantization on CD (he calls it "digital distortion"),
> misunderstanding the fact that it just isn't present when you use dither.
Yeah, so he's a twat. He works in hi-fi. What did you expect ?
Maybe it's all part of a big plan to get us to go back to valve radiograms ?
Graham
Phil Allison
"Jim Lesurf"
>
> You having mentioned that made me check, and I can confirm that the
> squarewave results in the HFN review of the CDP101 show no 'pre-ringing'.
> I
> haven't found a detailed spec for the CDP101, and can't recall any
> details.
> But it looks like it used the simple method of 16 bit DACs followed by an
> analogue filter.
** The output filter used in the famous Sony CDP 101 ( and several other
contemporary Sony models) was entirely passive - made by Murata and
consisting of an array of ceramic resonators.
Response was - dB at 20 kHz, sloping at -100dB per octave after that.
No kidding, the result was *zero* spurious supersonic signals despite no
use of oversampling.
> Above said, what I don't know is how monotonic or linear the Sony DACs
> were.
** Stop bragging about your monumental ignorance - you pathetic, pommy PITA
pommy wanker.
Arny posted the info here, in this SAME thread, on June 19th.
http://www.pcavtech.com/play-rec/Sony_CDP-101/index.htm#DR_DA
THD = circa 0.002% - including all noise sources.
It was as linear as all hell.
..... Phil.
Phil Allison
"Phil Allison"
**Typo:
> Response was -1dB at 20 kHz, sloping at -100dB per octave after that.
..... Phil
Eeyore
Phil Allison wrote:
> and consisting of an array of ceramic resonators.
THAT's why it sounded so awful !
Graham
Eeyore
Phil Allison wrote:
> "Phil Allison"
>
> **Typo:
>
> > Response was -1dB at 20 kHz,
CRAP. That's readily audible.
Don Pearce
Can you imagine the phase response and group delay of an analogue filter
that steep?
d
Dave Plowman (News)
Eeyore <rabbitsfriend...@hotmail.com> wrote:
> Phil Allison wrote:
It might be to your dog, listening to sine waves. But 1dB down at 20k
won't make any audible difference to any real world audio signal.
--
*Parenthetical remarks (however relevant) are (usually) unnecessary *
David Looser
news:4fb27ee...@davenoise.co.uk...
> In article <485BDC36...@hotmail.com>,
> Eeyore <rabbitsfriend...@hotmail.com> wrote:
>
>
>> Phil Allison wrote:
>
>> > "Phil Allison"
>> >
>> > **Typo:
>> >
>> > > Response was -1dB at 20 kHz,
>
>> CRAP. That's readily audible.
>
> It might be to your dog, listening to sine waves. But 1dB down at 20k
> won't make any audible difference to any real world audio signal.
>
Absolutely. How many humans can even hear 20k, let alone notice a 1dB drop.
David.
Don Pearce
If this were a first order filter you could probably hear the resultant
half dB approx. at 10kHz. I think I may be able to do that. But it is
seventeenth order or so, and is therefore flat to well beyond 16kHz.
That makes the un-flatness definitely inaudible.
d
David Looser
news:P96dnaKxnrs...@posted.plusnet...
>
> If this were a first order filter you could probably hear the resultant
> half dB approx. at 10kHz. I think I may be able to do that.
Do you? I'm amazed.
David.
Don Pearce
Probably not with music, but I've just tried it with noise, and it is no
problem at all. Interestingly, I also tried a 17th order Butterworth
filter 3dB down at 20kHz, and although the effect is subtle, I can
reliably identify it.
d
John Phillips
> In article <slrng5mk67....@linux.mainly.me.uk>, John Phillips
><news...@DontUseThis.mainly.me.uk> wrote:
>> In fact on the specific issue of digital processing with or without
>> dither and the effect on resolution in "reverb tails", since the CDP-101
>> had only analogue reconstruction filters there seems to be no
>> possibility to blame the player - only the CD mastering.
>
> You having mentioned that made me check, and I can confirm that the
> squarewave results in the HFN review of the CDP101 show no 'pre-ringing'. I
> haven't found a detailed spec for the CDP101, and can't recall any details.
http://www.adrian-kingston.com/CDP-101.htm purports to have details and
partial circuit diagrams.
--
John Phillips
John Phillips
> Eeyore wrote:
>> Phil Allison wrote:
>>> and consisting of an array of ceramic resonators.
>>
>> THAT's why it sounded so awful !
>
> that steep?
While such an extreme phase respose offends my engineering sensibilities
I still have not found credible references to tell me about the audibility
of phase shifts. If anyone knows of such material I would be interested.
--
John Phillips
David Looser
other without knowing which it was, would you be able to identify it?
David.
Eeyore
Don Pearce wrote:
> Eeyore wrote:
> > Phil Allison wrote:
> >
> >> and consisting of an array of ceramic resonators.
> >
> > THAT's why it sounded so awful !
>
> Can you imagine the phase response and group delay of an analogue filter
> that steep?
Don't even get me started. Why do you think there were Apogee filter
upgrades for PCM3324As and the like ?
WTF no-one chose a sensible sampling frequency and a half sensible bit depth
is forever beyond me.
20 bit and 60 kHz would have done nicely.
Graham
Eeyore
"Dave Plowman (News)" wrote:
> Eeyore <rabbitsfriend...@hotmail.com> wrote:
> > Phil Allison wrote:
> > > "Phil Allison"
> > >
> > > **Typo:
> > >
> > > > Response was -1dB at 20 kHz,
>
> > CRAP. That's readily audible.
>
> It might be to your dog, listening to sine waves. But 1dB down at 20k
> won't make any audible difference to any real world audio signal.
I can hear it, at least certainly used to be able to.
Just because YOU'RE deaf, don't assume everyone else is.
Graham
Eeyore
David Looser wrote:
> Absolutely. How many humans can even hear 20k, let alone notice a 1dB drop.
I used to be able to 'hear' - more accurately be aware of - at least 24 kHz.
Designing the CD spec around old deaf cunts was the worst move ever.
Graham
Eeyore
Don Pearce wrote:
> If this were a first order filter you could probably hear the resultant
> half dB approx. at 10kHz. I think I may be able to do that. But it is
> seventeenth order or so, and is therefore flat to well beyond 16kHz.
> That makes the un-flatness definitely inaudible.
I'm so pleased to hear that.
And when was yout hearing last tested ?
Graham
Eeyore
David Looser wrote:
> "Don Pearce" <nos...@nospam.com> wrote
> >
> > If this were a first order filter you could probably hear the resultant
> > half dB approx. at 10kHz. I think I may be able to do that.
>
> Do you? I'm amazed.
I'm not. In fact I reckon almost ALL the equipment differences associated
with alleged 'speed, pace, depth' and you know all the other fuck all crap
explanations are merely subtle frequency response variations.
But the scientific explanation is too BORING of course.
Graham
Eeyore
John Phillips wrote:
> http://www.adrian-kingston.com/CDP-101.htm purports to have details and
> partial circuit diagrams.
CDP-101 ?
You want me to throw up ?
Graham
Eeyore
John Phillips wrote:
> While such an extreme phase respose offends my engineering sensibilities
> I still have not found credible references to tell me about the audibility
> of phase shifts. If anyone knows of such material I would be interested.
Try your hearing.
Graham
Phil Allison
"Eeysore Raving Nut Case Pommy Prick "
>> "Phil Allison"
>>
>> **Typo:
>>
>> > Response was -1dB at 20 kHz,
>
> CRAP. That's readily audible.
** No it ain't - you fucking trolling idiot.
...... Phil
Phil Allison
"Eeysore Criminally Insane Pile of Pommy Shit "
> You want me to throw up ?
** Nah - just chuck your stupid, fat arse off the nearest high bridge.
...... Phil
Eeyore
Phil Allison wrote:
But you're DEAF. Of course you couldn't hear it.
Graham
Eeyore
Phil Allison wrote:
Well ... for you I gather Sydney has a suitable example.
Graham
Phil Allison
" Graham Stevenson = Raving Nut Case Pommy Cunt "
>> "Phil Allison"
>>
>> **Typo:
>>
>> > Response was -1dB at 20 kHz,
>
> CRAP. That's readily audible.
** No it ain't - you fucking trolling idiot.
..... Phil
Eeyore
Phil Allison wrote:
DEAF CUNT>
Phil Allison
" Graham Stevenson = Raving Nut Case Pommy Cunt "
>> "Phil Allison"
>>
>> **Typo:
>>
>> > Response was -1dB at 20 kHz,
>
> CRAP. That's readily audible.
** No it ain't - you fucking trolling idiot.
..... Phil
Phil Allison
" Graham Stevenson = Raving Nut Case Pommy Cunt "
>> "Phil Allison"
>>
>> **Typo:
>>
>> > Response was -1dB at 20 kHz,
>
> CRAP. That's readily audible.
** No it ain't - you fucking trolling idiot.
..... Phil
Don Pearce
> "Don Pearce" <nos...@nospam.com> wrote in message
> news:CbmdnThhsKfVmsHV...@posted.plusnet...
>> David Looser wrote:
>>> "Don Pearce" <nos...@nospam.com> wrote in message
>>> news:P96dnaKxnrs...@posted.plusnet...
>>>> If this were a first order filter you could probably hear the resultant
>>>> half dB approx. at 10kHz. I think I may be able to do that.
>>> Do you? I'm amazed.
>>>
>>> David.
>> Probably not with music, but I've just tried it with noise, and it is no
>> problem at all. Interestingly, I also tried a 17th order Butterworth
>> filter 3dB down at 20kHz, and although the effect is subtle, I can
>> reliably identify it.
>>
> This, presumably, is an A-B test. If you were presented with just one or the
> other without knowing which it was, would you be able to identify it?
>
> David.
>
>
Not in a million years.
d
Dave Plowman (News)
Eeyore <rabbitsfriend...@hotmail.com> wrote:
> "Dave Plowman (News)" wrote:
> > Eeyore <rabbitsfriend...@hotmail.com> wrote:
> > > Phil Allison wrote:
> > > > "Phil Allison"
> > > >
> > > > **Typo:
> > > >
> > > > > Response was -1dB at 20 kHz,
> >
> > > CRAP. That's readily audible.
> >
> > It might be to your dog, listening to sine waves. But 1dB down at 20k
> > won't make any audible difference to any real world audio signal.
> I can hear it, at least certainly used to be able to.
A 1dB change at 20k? I think not.
> Just because YOU'RE deaf, don't assume everyone else is.
I certainly don't make extravagant claims from behind my keyboard.
> Graham
--
*Why can't women put on mascara with their mouth closed?
Dave Plowman (News)
Eeyore <rabbitsfriend...@hotmail.com> wrote:
> David Looser wrote:
You should really do some research on the subject instead of bandying
around figures you obviously don't understand the meaning of in practical
terms.
> Graham
--
*People want trepanners like they want a hole in the head*
Dave Plowman (News)
Eeyore <rabbitsfriend...@hotmail.com> wrote:
> WTF no-one chose a sensible sampling frequency and a half sensible bit
> depth is forever beyond me.
> 20 bit and 60 kHz would have done nicely.
It was designed around the semi-pro video recorders of the day.
However, even your golden ears wouldn't tell the difference between 16 and
20 bit. 14 bit is where most cease to notice any difference.
And what on earth is the point in worrying about frequencies way above the
uppermost harmonics of any musical instrument?
--
*Does fuzzy logic tickle? *
Jim Lesurf
Pearce
<nos...@nospam.com> wrote:
> David Looser wrote:
> > "Don Pearce" <nos...@nospam.com> wrote in message
> > news:P96dnaKxnrs...@posted.plusnet...
> >> If this were a first order filter you could probably hear the
> >> resultant half dB approx. at 10kHz. I think I may be able to do that.
> >
> > Do you? I'm amazed.
> Probably not with music, but I've just tried it with noise, and it is no
> problem at all.
That does not mean you can hear the "half dB at 10kHz", since you may well
be hearing the loss of the higher frequencies.
Slainte,
Jim
--
Change 'noise' to 'jcgl' if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scots_Guide/intro/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html
Jim Lesurf
> "Dave Plowman (News)" wrote:
> > Eeyore <rabbitsfriend...@hotmail.com> wrote:
> > > Phil Allison wrote:
> > > > "Phil Allison"
> > > >
> > > > **Typo:
> > > >
> > > > > Response was -1dB at 20 kHz,
> >
> > > CRAP. That's readily audible.
> >
> > It might be to your dog, listening to sine waves. But 1dB down at 20k
> > won't make any audible difference to any real world audio signal.
> I can hear it, at least certainly used to be able to.
It is certainly wiser to claim you *used* to be able to do something. That
way even if you were put to the test now, and didn't do what was claimed,
your explanation would be to hand. :-)
> Just because YOU'RE deaf, don't assume everyone else is.
From what you say, I presume you find it intolerable to listen without
either doing so in an anechoic chamber, or using a clamp to keep your ears
in the same place all the time you listen... or do you only use headphones
because all room acoustics are unacceptable to you? :-)
Jim Lesurf
<rabbitsfriend...@hotmail.com> wrote:
> Phil Allison wrote:
> > and consisting of an array of ceramic resonators.
> THAT's why it sounded so awful !
Are you now claiming that the use of "ceramic resonators" caused you to
hear it "trunkating the tails" of reverb?
Don Pearce
> In article <CbmdnThhsKfVmsHV...@posted.plusnet>, Don
> Pearce
> <nos...@nospam.com> wrote:
>> David Looser wrote:
>>> "Don Pearce" <nos...@nospam.com> wrote in message
>>> news:P96dnaKxnrs...@posted.plusnet...
>>>> If this were a first order filter you could probably hear the
>>>> resultant half dB approx. at 10kHz. I think I may be able to do that.
>>> Do you? I'm amazed.
>
>
>> Probably not with music, but I've just tried it with noise, and it is no
>> problem at all.
>
> That does not mean you can hear the "half dB at 10kHz", since you may well
> be hearing the loss of the higher frequencies.
>
> Slainte,
>
> Jim
>
Quite possible. But I suspect that the difference I hear is closer to 10
than 20.
d
Eeyore
"Dave Plowman (News)" wrote:
> Eeyore <rabbitsfriend...@hotmail.com> wrote:
> > WTF no-one chose a sensible sampling frequency and a half sensible bit
> > depth is forever beyond me.
>
> > 20 bit and 60 kHz would have done nicely.
>
> It was designed around the semi-pro video recorders of the day.
Not at all. Both Ampex and 3M had reel-to-reel digital recorders with higher
sampling rates.
Graham
Eeyore
David Looser wrote:
> "Eeyore" wrote
> > Arny Krueger wrote:
> >
> >> The noise floor of a well-made recording is on the order of 75-80 dB.
> >
> > Have you gone completely MAD ?
> >
> > I can beat you by easily 50dB.
>
> Do you do all your recording in an anechoic chamber then?
What do you think the noise floor of a competently designed studio is ?
Graham
Eeyore
Jim Lesurf wrote:
> Arny Krueger
>
> > The noise floor of a well-made recording is on the order of 75-80 dB.
> > Below that is the noise floor, usually from analog (thermal) sources.
> > This is many times more than is required to properly dither a proper 16
> > bit conversion.
>
> I'd be interested in seeing data on the noise performance of studio mics
> and preamps, etc.
Neumann TLM103. Equivalent noise floor of 7dBA
http://www.neumann.com/?lang=en&id=current_microphones&cid=tlm103_data
Dynamic range of the microphone amplifier (A-weighted) 131 dB
Graham
Don Pearce
I think Arny meant S/N ratio rather than noise floor. A decent studio
will be somewhere around the 20dB mark. It is the exceptional studio
that is much below that, and you won't find it in a city.
d
Arny Krueger
message news:4fb1987...@davenoise.co.uk
> In article <48599466...@hotmail.com>,
> Eeyore <rabbitsfriend...@hotmail.com> wrote:
>>> Yup. Anything that starts off life at a microphone is
>>> unlikely to do very much better. And most recordings
>>> use several microphones...
>
>> Really good microphones have equivalent acoustic noise
>> levels of well below 20 dB.
>
> There's rather more to the average chain than just the
> microphone.
Based on my experiences with live recording in several dozen different
venues, the microphones, even those with noise in the 18 to 20 dB range,
are usually quieter than the venue by quite a bit. If it wasn't for the
venues and the performers, recodrings with dynamic range of up to 90 dB
would be pretty common.
Arny Krueger
message news:4859AFF6...@hotmail.com
> "Dave Plowman (News)" wrote:
>
>> Eeyore wrote:
>
> Someone else (edited out) wrote.
>
>>>> Yup. Anything that starts off life at a microphone is
>>>> unlikely to do very much better. And most recordings
>>>> use several microphones...
>>
>>> Really good microphones have equivalent acoustic noise
>>> levels of well below 20 dB.
>>
>> There's rather more to the average chain than just the
>> microphone.
>
> my figures are wrong.
That will be herd, because Graham you are correct.
Mic preamps that will not materially add to the noise of a mic with EIN on
the order of 20 dB are pretty common. Digitizing the output of a mic preamp
without adding additional noise does not require costly converters any more.
Arny Krueger
message news:48599399...@hotmail.com
> Arny Krueger wrote:
>
>> The earliest CD players had converters good enough to
>> demonstrate dynamic range on the order of 93 dB, which
>> is pretty close to the theoretical max:
>
> Oh come on !
>
> The earliest CD players were utter SHITE. Esp the
> CDP-101. Truncated reverb tails is what I remember
> especially.
http://www.pcavtech.com/play-rec/Sony_CDP-101/index.htm
shows that a properly-operating CDP 101 does not have serious issues with
dynamic range.
However, the DACs in the CDP 101 had a possible failure mode that might
explain what you heard.
A CDP101 contained 1 rather fast, rather precise 8 bit DAC. It is pretty
well known that the DAC was time-shared between the L and R channels. What
is not so well known is the fact that the DAC did 2 conversions per 16 bit
sample. If memorys serves, the first time period, the high order 8 bits were
converted to analog and gated into an integrator. During the second time
period, the low order 8 bits bits were converted to analog and gated into
the same integrator, but this time the voltage was divided by 256.
The voltage that was read out of the integrator was the sum of the two
conversions, but the second conversion was scaled by 256. The integrator
was then zeroed out. The same two conversions were done with data from the
other channel.
If memory does not serve, I have the order the conversions reversed. ;-)
BTE, this means that the LSB of the 8 bit DAC was really very precise for
being an 8 bit DAC. The division by 256 also needed to be very precise. I'm
under the impression that this slightly odd methodology was frequently used
in the early days of digital audio.
Any errors in setting the division by 256 would cause significant
nonlinearity.
Arny Krueger
> In article <48599399...@hotmail.com>,
> Eeyore <rabbitsfriend...@hotmail.com> wrote:
>> The earliest CD players were utter SHITE. Esp the
>> CDP-101. Truncated reverb tails is what I remember
>> especially.
> You mean fading out the track early in the CD mastering
> to try and stop you hearing the tape hiss?
I have two functional CDP101s at my disposal. If
http://www.pcavtech.com/play-rec/Sony_CDP-101/index.htm
doesn't convince, I might be convinced to do some fade-to-zero tests. The
CDP 101 is not at its best playing CD-Rs, but at least one of the two does
well enough if I do the burning at a low speed.
Arny Krueger
news:4fb1d05...@audiomisc.co.uk
>
>>> The earliest CD players had converters good enough to
>>> demonstrate dynamic range on the order of 93 dB, which
>>> is pretty close to the theoretical max:
>
>> Oh come on !
>
>> CDP-101. Truncated reverb tails is what I remember
>> especially.
>
>> memory of that.
>
> Prompted by what you say, I had a look at the first
> review of the CDP101 in Hi Fi News. (Martin Colloms,
> March 1983).
>
> This shows measurements of the nominal THD with test
> signals down to -80 dBFS.
Pretty much the same thing as I measured and posted at
http://www.pcavtech.com/play-rec/Sony_CDP-101/index.htm
This test was done in 1999.
> Given this, it seems dubious that what you claim was due
> to the player trunkating the reverb. The player MC tested
> seemed to perform without trunkating signals well below
> what you be hearing above noise on an LP.
In another post I describe the CDP 101's unusual use of just one very
precise 8 bit converter. If there were errors (e.g. bad parts) in this
process, what Graham describes might happen.
Arny Krueger
message news:485BDC36...@hotmail.com
> Phil Allison wrote:
>
>> "Phil Allison"
>>
>> **Typo:
>>
>>> Response was -1dB at 20 kHz,
>
> CRAP. That's readily audible.
The Clark/Masters CD player tests
Masters, Ian G. and Clark, D. L., "Do All CD Players Sound the Same?",
Stereo Review, pp.50-57 (January 1986)
reported that the CDP 101 could be soncially distinguished from other
players when listening to certain program material, but not others.
Probable cause is the 3/4 dB drop in frequency response starting around 6
KHz.
http://www.pcavtech.com/play-rec/Sony_CDP-101/index.htm
Arny Krueger
message news:485D7A8F...@hotmail.com
30-ish dB.
Besides, putting living, breathing musicians in the studio will ruin it if
it is much better than that.
Arny Krueger
> In article
> <sNGdnYvXWa3v7sTV...@comcast.com>, Arny
> Krueger
> <ar...@hotpop.com> wrote:
>> "John Phillips" <news...@DontUseThis.mainly.me.uk>
>> wrote in message
>> news:slrng5g1c7....@linux.mainly.me.uk
>>> On 2008-06-16, Jim Lesurf <no...@audiomisc.co.uk> wrote:
>
>>>
>>> IIRC Lipschitz and Vanderkooy were publishing about
>>> dither in JAES in about 1984 and just after. Although
>>> dither had been know for a long time I suspect you are
>>> right that noise floors for material transferred to CD
>>> were probably sufficient in the early days of CD
>>> (1982-ish) to render external dither unnecessary.
>
>> AFAIK Vanderkooy and Lipshitz were knowingly publishing
>> old news, in an effort to overcome some pretty strange
>> false claims that were being circulated at the time by
>> people who should have known better.
> That is also my recollection. I can't remember when the
> first work on dither was done, but I think it was
> produced a long time ago. Hence there really isn't much
> excuse for someone writing magazine articles like NKs not
> to understand it. I was certainly reading about such
> matters long ago.
The author that V&L were "answering" was a professor Professor PB Fellgett,
and published in 1981.
I comment on a posting of it in this post:
http://groups.google.com/group/rec.audio.opinion/msg/9de7d88bbec10f81
Much of its contents are quoted.
> I'd be interested in seeing data on the noise performance
> of studio mics and preamps, etc. If I recall correctly,
> their bandwidths also may cast some doubt on the idea
> that LP recordings provide wide ultrasonic bandwidths of
> genuine recorded sounds. (As distinct from distortion
> products, etc.)
The quietest mics have A-weighted noise equivalent to an acoustical level
that is just under 10 dB. Most serious mics have A-weighted noise equivalent
to an acoustical level that is 20 dB or less. The weighting curve is
significant because the spectral contents of microphone internal noise can
vary depending on the technology used to build the mic.
IME it is not difficult to find mic preamps and converters that are quiet
enough that they don't materially add to the noise coming out of a typical
capacitor microphone.
Arny Krueger
message news:485D7C79...@hotmail.com
That's real good. The Rode NT1-A is a bit more economical and speced to have
self noise of 5 dB.
The fly in the ointment is coming up with a musical acoustical source that
goes up to 138 dB when played in a typical sort of way.
Phil Allison
"Arny Krueger"
> "Eeyore"
>> Phil Allison wrote:
>>
>>> "Phil Allison"
>>>
>>> **Typo:
>>>
>>>> Response was -1dB at 20 kHz,
>>
>> CRAP. That's readily audible.
>
> The Clark/Masters CD player tests
>
> Masters, Ian G. and Clark, D. L., "Do All CD Players Sound the Same?",
> Stereo Review, pp.50-57 (January 1986)
>
> reported that the CDP 101
** Do try and follow a thread - Arny.
My post in NOT about the CDP101.
...... Phil
Eeyore
Don Pearce wrote:
> Eeyore wrote:
> > David Looser wrote:
> >> "Eeyore" wrote
> >>> Arny Krueger wrote:
> >>>
> >>>> The noise floor of a well-made recording is on the order of 75-80 dB.
> >>> Have you gone completely MAD ?
> >>>
> >>> I can beat you by easily 50dB.
> >> Do you do all your recording in an anechoic chamber then?
> >
> > What do you think the noise floor of a competently designed studio is ?
>
> I think Arny meant S/N ratio rather than noise floor.
I sense evasion here.
> A decent studio will be somewhere around the 20dB mark.
Not in my book.
> It is the exceptional studio that is much below that, and you won't find it
> in a city.
Yes you can when it's really good and it'll be 10-12 dBA. Not all parts of
cities are that noisy and it's amazing what clever construction methods can
do.
The biggest problem is keeping the noise of the air conditioning down
actually.
Graham
Eeyore
Arny Krueger wrote:
> "Eeyore" <rabbitsfriend...@hotmail.com> wrote in
> > David Looser wrote:
> >> "Eeyore" wrote
> >>> Arny Krueger wrote:
> >>>
> >>>> The noise floor of a well-made recording is on the
> >>>> order of 75-80 dB.
> >>>
> >>> Have you gone completely MAD ?
> >>>
> >>> I can beat you by easily 50dB.
> >>
> >> Do you do all your recording in an anechoic chamber then?
> >
> > What do you think the noise floor of a competently
> > designed studio is ?
>
> 30-ish dB.
Good Lord ! You're WAY off the mark. 30dB is NOISY to me. I'm talking about
proper commercial high-end music recording facilities that have cost MILLIONS
to build.
You need to visit some top London studios I know. The silence is deafening.
Graham
Eeyore
Arny Krueger wrote:
> "Eeyore" wrote
What fly would that be ?
Have you any idea what PEAK acoustic levels some unamplified instruments can
reach ?
Graham
Eeyore
Arny Krueger wrote:
> IME it is not difficult to find mic preamps and converters that are quiet
> enough that they don't materially add to the noise coming out of a typical
> capacitor microphone.
These days certainly not a problem whatever.
Graham
Eeyore
Eeyore wrote:
In fact, taking that TLM103 example, with +13dBu ? max out, it may not even need
any preamp at all to connect it to a converter if intending to use it at high
SPLs.
Graham
Phil Allison
"Eeysore the Fucking LIAR"
> Jim Lesurf wrote:
>>
>> I'd be interested in seeing data on the noise performance of studio mics
>> and preamps, etc.
>
> Neumann TLM103. Equivalent noise floor of 7dBA
** The CCIR "equivalent noise level " figure is 17.5 dB.
> http://www.neumann.com/?lang=en&id=current_microphones&cid=tlm103_data
** However - the s/n ratio quoted is mere ** 76.5 dB ** CCIR relative to a
SPL of 94 dB.
94 dB SPL is about the max level of a singing voice at 50 cm and is rather
more than the level from an acoustic guitar at that same distance.
...... Phil
Eeyore
Phil Allison wrote:
> "Eeysore the Fucking LIAR"
> > Jim Lesurf wrote:
> >>
> >> I'd be interested in seeing data on the noise performance of studio mics
> >> and preamps, etc.
> >
> > Neumann TLM103. Equivalent noise floor of 7dBA
>
> ** The CCIR "equivalent noise level " figure is 17.5 dB.
Unweighted of course.
Do you think unweighted measurements are relevant when close to the auditory
theshold ? I'd have thought they might actually OVER estimate them.
As usual, you're simply being an ass.
Now bugger off.
Graham
Phil Allison
> Jim Lesurf wrote:
>> >>
>> >> I'd be interested in seeing data on the noise performance of studio
>> >> mics
>> >> and preamps, etc.
>> >
>> > Neumann TLM103. Equivalent noise floor of 7dBA
>>
>> ** The CCIR "equivalent noise level " figure is 17.5 dB.
** Replacing the snipped link.
http://www.neumann.com/?lang=en&id=current_microphones&cid=tlm103_data
> Unweighted of course.
** Absolutely not true !!!!!!!!!!!
Read your *OWN* damn link !!!
You lying, ASD fucked, criminal pommy CUNT !!
The CCIR 468-3 weighing curve is nothing like flat.
http://en.wikipedia.org/wiki/ITU-R_468_noise_weighting
It flatters condenser mics by removing the majority of their LF noise
utput - more so than A weighting does.
..... Phil
Eeyore
Phil Allison wrote:
> It flatters condenser mics by removing the majority of their LF noise
> utput - more so than A weighting does.
Ever heard of the Fletcher-Munson curve ?
Just how sensitive do you think YOUR ear is to LF at 7dB ?
Ler me answer that for you. It'd below threshold, i.e. irrelevant.
Graham
Phil Allison
FUCKING INSANE OVER SNIPPER !!!!!!!!!!!!! "
> Jim Lesurf wrote:
>> >>
>> >> I'd be interested in seeing data on the noise performance of studio
>> >> mics and preamps, etc.
>> >
>> > Neumann TLM103. Equivalent noise floor of 7dBA
>>
>> ** The CCIR "equivalent noise level " figure is 17.5 dB.
** Replacing the snipped link.
http://www.neumann.com/?lang=en&id=current_microphones&cid=tlm103_data
> Unweighted of course.
** Absolutely not true !!!!!!!!!!!
Read your *OWN* damn link !!!
You lying, ASD fucked, criminal pommy CUNT !!
The CCIR 468-3 weighing curve is nothing like flat.
http://en.wikipedia.org/wiki/ITU-R_468_noise_weighting
It flatters condenser mics by removing the majority of their LF noise
output - more so than A weighting does.
..... Phil
Phil Allison
"Eeysore" <rabbitsfriend...@hotmail.com>
** Graham Stevenson has Asperger's syndrome PLUS narcissistic personality
disorder .
THAT's why the steaming, great pommy fuckwit sounds so awful !
...... Phil
Phil Allison
"Don Pearce"
>
> Can you imagine the phase response and group delay of an analogue filter
> that steep?
** One WOULD have to *imagine* it - cos it certainly ain't audible on
music or speech.
You need to go look up the BBC and Philips / Sony research on the
detectability of audio bandwidth limiting. They did extensive "double
blind' testing of the audibility of such brick wall filters.
Real engineers rely only on facts and evidence - not personal hunches and
naive hypotheses.
Only the mentally defective, self aggrandising charlatans and assorted
fuckwits like Stevenson and YOU do that.
..... Phil
Don Pearce
If you are measuring in dBa then sure, no problem. Most of the residual
SPL is structure-borne LF stuff that is seriously expensive to eliminate.
d
Phil Allison
"John Phillips"
>
> While such an extreme phase respose offends my engineering sensibilities
> I still have not found credible references to tell me about the audibility
> of phase shifts. If anyone knows of such material I would be interested.
** The only places you will find it is in professional journals published
decades ago.
Wireless World carried a few articles on the topic of the detectability
audio band brick wall filters in relation to digital audio in the late 70s
and early 80s. Firstly in regard to the BBC's 13 bit FM broadcast signal
distribution system and later in relation to the CD audio standard.
FM stereo broadcasts contain a brick wall filters at 15 kHz and CD has
shifted that up to circa 20 kHz.
..... Phil
Phil Allison
"Eeysore Steaming Great Pommy Charlatan & Fuckwit "
>
> John Phillips wrote:
>
>> While such an extreme phase respose offends my engineering sensibilities
>> I still have not found credible references to tell me about the
>> audibility
>> of phase shifts. If anyone knows of such material I would be interested.
>
** That's what all the fuckwit audiophools say.
Then do nothing of the sort.
...... Phil
Phil Allison
"Eeysore Criminal Pommy CHARLATAN"
> Don't even get me started.
** LOL - would sure like to FINISH you once and for all
- you vile fake.
> Why do you think there were Apogee filter
> upgrades for PCM3324As and the like ?
** Yawn....
Snake oil remedies sold for sky high prices made lots of money for those
crooks.
BTW:
Apogee was begun and owned by an Australian wanker called Bruce Jackson.
He started a PA hire company ( Jands ) here in Sydney in the late 60s, then
sold it and went to the USA to become sound guy for Elvis Presley in the
early 1970s.
That is when I met up with him in Sydney.
Wot a smug and arrogant wanker.
..... Phil
David Looser
news:arednVJD6snDHsDV...@comcast.com...
>
> Based on my experiences with live recording in several dozen different
> venues, the microphones, even those with noise in the 18 to 20 dB range,
> are usually quieter than the venue by quite a bit. If it wasn't for the
> venues and the performers, recodrings with dynamic range of up to 90 dB
> would be pretty common.
>
Exactly, hence my question to Graham (which he never answered) as to whether
he made all his recordings in an anechoic chamber. The notion of making
recordings without performers or a venue is a pretty strange one. There is
also the question of where and how this recording is going to be played
back. The ratio between the loudest sound that the listener can tolerate and
the background noise of even a specialy constructed listening room is not
going to be more than around 75-80 dB.
David.
Eeyore
Phil Allison wrote:
> The CCIR 468-3 weighing curve is nothing like flat.
>
> http://en.wikipedia.org/wiki/ITU-R_468_noise_weighting
I quoted the *A* weighted figure you moronic shite.
Graham
Arny Krueger
message news:485DA358...@hotmail.com
> Arny Krueger wrote:
>
>> "Eeyore" <rabbitsfriend...@hotmail.com> wrote
>> in
>>> David Looser wrote:
>>>> "Eeyore" wrote
>>>>> Arny Krueger wrote:
>>>>>
>>>>>> The noise floor of a well-made recording is on the
>>>>>> order of 75-80 dB.
>>>>>
>>>>> Have you gone completely MAD ?
>>>>>
>>>>> I can beat you by easily 50dB.
>>>>
>>>> Do you do all your recording in an anechoic chamber
>>>> then?
>>>
>>> What do you think the noise floor of a competently
>>> designed studio is ?
>> 30-ish dB.
> Good Lord ! You're WAY off the mark. 30dB is NOISY to me.
> I'm talking about proper commercial high-end music
> recording facilities that have cost MILLIONS to build.
You said "competently-designed", not SOTA.
> You need to visit some top London studios I know. The
> silence is deafening.
Most studio music is made in far lesser studios.
Also, a lot of that silence goes away after you add living, breathing
musicians. Just sitting there, they make noise.
Eeyore
Don Pearce wrote:
> Eeyore wrote:
> > Don Pearce wrote:
> >> Eeyore wrote:
> >>> David Looser wrote:
> >>>> "Eeyore" wrote
> >>>>> Arny Krueger wrote:
> >>>>>
> >>>>>> The noise floor of a well-made recording is on the order of 75-80 dB.
> >>>>> Have you gone completely MAD ?
> >>>>>
> >>>>> I can beat you by easily 50dB.
> >>>> Do you do all your recording in an anechoic chamber then?
> >>> What do you think the noise floor of a competently designed studio is ?
> >> I think Arny meant S/N ratio rather than noise floor.
> >
> > I sense evasion here.
> >
> >
> >> A decent studio will be somewhere around the 20dB mark.
> >
> > Not in my book.
> >
> >
> >> It is the exceptional studio that is much below that, and you won't find it
> >> in a city.
> >
> > Yes you can when it's really good and it'll be 10-12 dBA. Not all parts of
> > cities are that noisy and it's amazing what clever construction methods can
> > do.
> >
> > The biggest problem is keeping the noise of the air conditioning down
> > actually.
>
> If you are measuring in dBa then sure, no problem. Most of the residual
> SPL is structure-borne LF stuff that is seriously expensive to eliminate.
PROVE IT. I hope you have the instrumentation. I hope for my part I can arrange
access to a suitable studio.
Graham
Arny Krueger
message news:485DA411...@hotmail.com
Reality. Remember Graham, I make 100's of live recordings in dozens of
venues every year.
> Have you any idea what PEAK acoustic levels some
> unamplified instruments can reach ?
Absolutely.
110 dB happens, and when it happens it hurts the hearing of the musicians.
130 dB takes an aircraft carrier launching jets, etc.
Eeyore
Phil Allison wrote:
> "Eeysore Steaming Great Pommy Charlatan & Fuckwit "
> > John Phillips wrote:
> >
> >> While such an extreme phase respose offends my engineering sensibilities
> >> I still have not found credible references to tell me about the
> >> audibility of phase shifts. If anyone knows of such material I would be
> interested.
> >
> > Try your hearing.
>
> ** That's what all the fuckwit audiophools say.
What do YOU use to listen with ?
Do you have a BNC inserted in the back of your neck ?
Graham