Legend acoustics Kantu, little treble?
Kong
test results really caught my eye. According to their pink noise
spectrum analysis, the response of the speakers was measured to be
45Hz-15kHz +/- 2dB. They also make note that “the tweeter rolls off
quite sharply above 15kHz”.
More interestingly, I’ve also heard two other speakers manufacturers
whose speakers exhibit such frequency responses (Sonique and Tannoy).
Since DVD-A and SACD can cater for much higher frequencies than the CD
(something like 50kHz), won’t these speakers be inadequate?
graham
Kong <wkk...@nospam.camtech.net.au> wrote in message
news:3A712528...@nospam.camtech.net.au...
i think that is why sony has made a special super tweeter deisigned to go
high into those regions of sound for their SACD players.
Kong
these speakers despite their inability to reproduce frequencies up to 20kHz.
What would be the use of DVD-A and SACD if people are happy with such a freq
response?
graham
people who hate horns and brass which are traditionally bright sounding
instruments. The funny thing here is that these are usually what they sound
like in real life.
I am not a big fan of Legend speakers because of this fact. they have a very
tight, controlled sound that i find bland and unemotional at times. Remember
speakers cannot reproduce sounds exactly as they should. They alter the
sound. the trick is finding a speaker which alters the sound to your liking.
Legend is not one i like while KRIX is.
Kong <wkk...@nospam.camtech.net.au> wrote in message
news:3A729727...@nospam.camtech.net.au...
Rick Stadelmaier
Don't get too hung up on DVD-A and SACD having frequencies up to 50k.
Sure on paper they have it, but you will find there is little
information above 20k. (this is of course not to say they don't have
other advantages)
Furthermore, most of us can't here much past 16-18k, with some reaching
as high as 22k when there young.
As far as the Legends speakers, Don't worry about the specs, if you like
the sound of em', buy em'.
I doubt you'll go far wrong.
Rick.
Equinox Audio
http://www.equinoxaudio.com.au
equ...@pip.com.au
Sent via Deja.com
http://www.deja.com/
Rick Stadelmaier
Sony claim extension to 100k for it's super tweeter, this is optimistic
to say the least.
Aus hi-fi reviewed this tweeter a few months back, they didn't publish
any measurements, only Sonys claimed data.
I wonder why?
Besides anything audible heard using this tweeter will be the overlap
from below 20k caused by the shallow crossover.
I find $4000 for a tweeter designed to produce frequencies that we can't
hear is a bit sus.
You be the judge.
Peter Groves
I've just checked the Legend website
http://www.legendspeakers.com.au/kantuspe.htm
They list the Kantu 2 frequency range as being 45-18khz, + or - 3db.
15khz sounds a bit low to me. Maybe it dips at some point.
As for DVDA and SACD, it is hard to say until we get some more
players, and music releases to play on them!
Regards
Peter.
Damien Smith
> test results really caught my eye. According to their pink noise
> spectrum analysis, the response of the speakers was measured to be
> 45Hz-15kHz +/- 2dB. They also make note that "the tweeter rolls off
> quite sharply above 15kHz".
>
> More interestingly, I've also heard two other speakers manufacturers
> whose speakers exhibit such frequency responses (Sonique and Tannoy).
Hmm...interesting. That would indeed explain why the Tannoy speakers that
I've heard have sounded 'dull'
Kong
Agreed. The Revolution and Mercury speakers sound BORING!
Andrew Summerton
I wouldn't be the least bit worried about it if I were you.
You will find that most tweeters, even the best, ie Focal, Dynaudio,
Vifa etc have some rolloff.
None of them go to 50khz, does that mean they are all inadequate? I
think not.
Whilst I am not at all familiar with the Kantu, 45 to 15khz at +-2db is
exceptionally good if you MUST go by techinical specs, at the end of
the day it is the sound that counts, so just listen.
In some cases, some rollof above 13 -14khz may actually be beneficial if
you have a poor quality CD or DVD player, to smoothing out some high
frequency hash.
Moral: don't worry too much about specs, they mean very little, just listen!
Rod Crawford
been away for the past week.
The dip in frequency response at 15 kHz in the Kantu is due to the cone
breaking up - it is then followed by a small peak at 17kHz (well controlled
because of the heavy damping) before the tweeter finally gives up the ghost.
Most soft dome tweeters are like this, though some are betters than others.
Tannoy tweeters typically die above about 12 kHz which is why I refused to
use them at Linn despite being under intense pressure to do so from a fellow
Scot.
Like ALL speakers, the Kantu is a compromise - I could have used (and indeed
tried) a metal dome tweeter which does not breakup until 25kHz but this is
usually followed by a very large peak which is undamped and to which some
people attribute the excessive brightness of some metal domes. Because the
Audax aerogel bass/mid-range drivers of the Kantus can sound bright in
poorer systems, the overall sound balance was found to be unacceptable
bright to most people in all but the smoothest front ends.
Even with a soft dome tweeter I would hardly call the Kantus 'dull'- though
they may be relative to some others, especially American speakers (eg
Klipsch) which I find unacceptably 'shrill'. The 'bite' in trumpets,
violins etc is due more to the 1-10 kHz range where the first harmonics
occur (and where the Kantus are exceptionally linear) than what happens
above 10 kHz - the latter range is more related to the 'air' around
instruments. This is certainly what I hear (even on the Kantus!) when I
play 96kHz CDs on a Pioneer 717 through a Sony 9000 processor.
However, speaker design (and purchase) is as much a subjective experience as
an objective one (I spend about 20% of design time on measurements and about
80% on listening). Whether it is very cost effective spending $4000 on a
'super-tweeter' for a $3000 speaker seems more doubtful. But as SACD etc
become more prevalent, speaker designers will undoubtedly have to change
their compromises to take the higher sampling rates into account.
Cheers
Rod
(Dr) Rod Crawford
for Legend Acoustics
"Fast, open, Australian speakers"
www.legendspeakers.com.au
Kong <wkk...@nospam.camtech.net.au> wrote in message
news:3A712528...@nospam.camtech.net.au...
VAF Research
all angles. The total Power Response of the speaker is a measure of the
total energy the speaker is putting into the room, not just the 'on axis'
stuff. What you hear in the room is a combination of the direct 'on axis'
sound from the speakers and the reverberant sound that is bouncing around
the room before it gets to your ears. If the harmonic balance of the
reverberant sound is grossly different from the harmonic balance of direct
sound then intelligibility will be compromised as well as the general 'tone'
of the overall sound. It is very complicated to optimise the power response
and most manufacturers don't seen to actually make measurements in this
regard but defer to educated guesses. If you listened in an anechoic
chamber the only thing important would be the on axis responses.
Best regards
Philip Vafiadis
VAF Research Pty Ltd
www.vaf.com.au
Kong <wkk...@nospam.camtech.net.au> wrote in message
news:3A810844...@nospam.camtech.net.au...
> Talking about speaker freq response, what makes some speakers great for
vocals?
>
> For example, I use the Corr's rendition of Everybody Hurts and Sarah
McLachlan's
>
> Angels a lot to test vocal performance of various speakers and some have
the
> ability
> to put her voice up front, clearly and bold. The VAF DC-X does this along
with
> the
> B&W 60x and the NHT SuperZeros/Ones.
>
> Other speakers, like the Missions 77x, DM302, Tannoy, Sonique sound boring
in
> comparison. Dead, dull and lifeless.
Rod Crawford
reverberant (total off axis - sometimes called power) response. However,
the crossover theory of Bullock from the early 1980s shows that it is
IMPOSSIBLE to get ALL of the direct, power and phase response correct
simultaneously except for first order crossovers which themselves have major
problems (of lobing, cone breakup etc). All speakers are an awkward
compromise because of the laws of physics (which only God can overcome)! Se
also my comments at the end of the 'centre channel' thread (again apologies
for the delay - I too some holidays)!
Regarding midrange quality (which is the main determinant, it is of female
voices, it is partly a flat frequency response (compromised as best possible
on and off axis) and partly the way the midrange driver breakup in the
midband which causes time delay ringing/smearing (shown in waterfall plots).
One reason we do not use polypropylene drivers (as some others do) is that
they are particularly bad in this respect. Whatever the faults of Legend
speakers (and I am more aware of their compromises than most) they are
generally favourably regarded in their mid-band, partly determined by the
use of specially-manufactured-for-us aerogel drivers.
Cheers
Rod
(Dr) Rod Crawford
for Legend Acoustics
"Fast, open, Australian speakers"
www.legendspeakers.com.au
VAF Research <phi...@vaf.com.au> wrote in message
news:95slas$pcn$1...@pinah.connect.com.au...
VAF Research
Rod Crawford <leg...@canberra.teknet.net.au> wrote in message
news:CpCg6.2$0s5...@nsw.nnrp.telstra.net...
> I agree with Phil that what we hear is a combination of direct and
> reverberant (total off axis - sometimes called power) response. However,
> the crossover theory of Bullock from the early 1980s shows that it is
> IMPOSSIBLE to get ALL of the direct, power and phase response correct
> simultaneously except for first order crossovers which themselves have
major
> problems (of lobing, cone breakup etc).
Yes, time aligned acoustically first order symmetrical arrays are an obvious
engineering choice, this is why I use them at VAF.
Cone break-up is not the 'beast' it once was, if you see our VAF DC-X design
we get around 8KHz out of the 210mm woofers with good off axis performance.
First orders, if executed well in conjunction with diffraction control can
be engineered to offer fewer lobes around the central axis. With regard to
lobing, I aim for a wide and even centre lobe and try to juggle the outer
ones to even up the total power response.
This is difficult to achieve and every year that goes by I keep buying more
and more test gear. The more data collected, though, requires seemingly
exponentially more analysis. Problems always seem to get bigger the more you
look into them....'bugger'...got to spend more money.
Rod Crawford
Hi Phil
You may get up to 8 kHz out of a 210 mm driver but I very much doubt that it
is without cone breakup - and so without some time smearing.
I did some measurements at Linn with a doppler interferometer (that's
serious money in test equipment!!) which showed that polypropylene 170 mm
cones start to breakup below 1kHz.
The waterfall plots of my 170 mm aerogel drivers (which are made of
carbon-fibre/kevlar and so about as stiff as you can get) suggest that they
start breaking below 2 kHz, though are well controlled by the gel coating.
Much of my design effort is spent trying to live with this!
Philip Vafiadis
it
> is without cone breakup - and so without some time smearing.
No need to doubt it. Evidence by way of the cumulative spectral decay
measurement is on our web site at www.vaf.com.au ...follow the links to the
DC-X then click on specifications...Check it out...it is very even and very
fast, and we use no electrical crossover on the woofer. The off axis data is
also available if you would like to see it. It is not on the web site but I
would be happy to e-mail it if you contact me at work on phi...@vaf.com.au
(Not here at home)
> I did some measurements at Linn with a doppler interferometer (that's
> serious money in test equipment!!) which showed that polypropylene 170 mm
> cones start to breakup below 1kHz.
Agreed, but we don't use polypropelene cones in any of our designs???
> The waterfall plots of my 170 mm aerogel drivers (which are made of
> carbon-fibre/kevlar and so about as stiff as you can get) suggest that
they
> start breaking below 2 kHz, though are well controlled by the gel coating.
> Much of my design effort is spent trying to live with this!
Yes, your measurements seem correct. We notice a gentle start at around
700Hz building through around 1500Hz (can't remember the exact numbers).
On your comments about cone stiffness, if the Aerogel cone was "as stiff as
it gets" the on axis response would not be anything like that of your Audax
Aerogel cone. Audax make the Aerogel cones in a process similar to
paper...an Aerogel slurry is sucked onto a perforated cone shaped former.
Among other things, the time in the slurry, and the pressure used, determine
the cone's total build thickness etc. The cone can also have differential
thickness if the locations of the perforations are redefined . Audax used to
use a PVA based 'goop' as a coating but that was severely effected by
humidity and moisture and was dropped in favour of the current coating. The
original cones and coating were also a little porous making only lossier
alignments possible. The coating to the cone that Audax now use is not a gel
either, as you had indicated, it is a plastic film (looks like cling wrap)
that is vaccume formed to the cone while it is still damp. Tiny bending
moments at the coil/cone junction remains a problem where fine resolution of
micro dynamic detail is required. It is an interesting use of existing
technology...and like all things has it's strengths and weaknesses, no pun
intended.
Best regards
Philip
Rick Stadelmaier
> > You may get up to 8 kHz out of a 210 mm driver but I very much doubt
that
> it
> > is without cone breakup - and so without some time smearing.
>
> No need to doubt it. Evidence by way of the cumulative spectral decay
> measurement is on our web site at www.vaf.com.au ...follow the links
to the
> DC-X then click on specifications...Check it out...it is very even and
very
> fast, and we use no electrical crossover on the woofer. The off axis
data is
> also available if you would like to see it. It is not on the web site
but I
> would be happy to e-mail it if you contact me at work on
phi...@vaf.com.au
I'm just curious Phillip, but what are your reasons to cross a 8" driver
at 8k? I see no real benefit to doing this, only a lot of drawbacks?
*Any* 8" will perform better crossed over at say 2-4k (or less), IME.
Enlighten me.
Oh can you e-mail me those off axis plots?
VAF Research
dimensions vs horn effects etc....this is how most people look at the
problem.
In the DC-X, a choice to use a high crossover for it's own sake was not a
factor. My goal was to stop problems at their very heart before they had
happened.
With this in mind, and in conjunction with a number of other engineering
aims, I engineered the propagation speed of sound through the cone to be
complimentary to the propagation of sound through the air, taking into
account the actual geometry of the cone. Take a look at the phase response
of the DC-X ( www.vaf.com.au follow links to DC-X then click
specifications). If the woofers behaved in a conventional fashion, this
exemplary phase performance would not be possible.
From here Rick, you will have to work it out yourself.... I don't want to
give too much away for free :^)
I will get the off axis info from the R&D system and send it to you...give
me a few days.
Best regards
Philip Vafiadis
VAF Research Pty Ltd
www.vaf.com.au
Rick Stadelmaier <rick_e...@my-deja.com> wrote in message
news:967a37$s1a$1...@nnrp1.deja.com...
Rick Stadelmaier
> You are probably thinking in terms of piston diameter vs wavelength vs
cone
> dimensions vs horn effects etc....this is how most people look at the
> problem.
Naturally.
> In the DC-X, a choice to use a high crossover for it's own sake was
not a
> factor. My goal was to stop problems at their very heart before they
had
> happened.
>
> With this in mind, and in conjunction with a number of other
engineering
> aims, I engineered the propagation speed of sound through the cone to
be
> complimentary to the propagation of sound through the air, taking into
> account the actual geometry of the cone. Take a look at the phase
response
> of the DC-X ( www.vaf.com.au follow links to DC-X then click
> specifications). If the woofers behaved in a conventional fashion,
this
> exemplary phase performance would not be possible.
>
> From here Rick, you will have to work it out yourself.... I don't want
to
> give too much away for free :^)
Thats fine Phillip, I am not here to critisise or question your designs,
I was merely curious as to why you would choose such a high x-over.
Besides, I'm not into the habit of copying anyones middle range designs,
there top end designs maybe.... ;)
Rod Crawford
I'm sorry but I do still have very strong doubts, particularly having looked
at the spectral decay (waterfall) plots of the DCX on your website.
The plots show strong evidence of breakup in the 1-2 kHz region and again in
the 3-8kHz region where there appear to be resonances (ringing) that take
nearly 2 ms to decay by -25dB. Assuming one is playing music at 85dB these
resonances would still be 60dB above the threshold of hearing and still very
audible.
Remembering that a 1kHz note has a period (cycle repeat time) of 1 ms, this
means that the ringing at this frequency occurs for 2 cycles to this level
of audibility (for a 2 ms decay); and 4 cycles at 2 kHz; 8 cycles at 4kHz;
16 cycles at 8 kHz etc. I would have thought that this would have caused
some degree of 'time smearing' and so some loss of intelligibility,
especially since it occurs in the upper midband where harmonics of voices
and notes are important, and where the human ear is most sensitive.
I suspect from my previous experience (I am a materials scientist as well as
a physicist) and from the above evidence that breakup of your cone is
occurring quite early (around 1 kHz) but is relatively well controlled by
the pads etc which I think you apply to the cones. Hence the good linearity
in frequency response, despite the resonances (I have seen some
polypropylene cones giving similar results), which enables you to use no
electrical crossover (though the work of Thiele and Small suggest mechanical
and electrical 'filters' are equivalent).
I agree that the aerogel drivers are not perfect (hence their challenge to
me a speaker designer)! However, they did move the technology envelope out
from where it had been and so allowed the potential for some improvement in
sound quality. Their main 'fault' is that of any very stiff driver - when
they do breakup they could do so uncontrollably but this is counteracted by
the 'gel' coating (and I worked with Audax to add more which our work showed
even better control). I also then add extra doping! This results in a
clean but smooth sound (breakups occur at higher frequencies because of
their stiffness but, like your drivers, when they do occur are very well
controlled). I suspect this may be what some people hear as a 'lack of
treble' in the Kantus - they may be used to hearing the lower treble 'hash'
in some speakers, caused either by uncontrolled breakup of the midrange unit
or by trying to use the tweeter too low.
Hope all this adds more light than heat!
Cheers
Rod
(Dr) Rod Crawford
for Legend Acoustics
"Fast, open, Australian speakers"
www.legendspeakers.com.au
ABN 32 812 648 096
Philip Vafiadis <phi...@camtech.net.au> wrote in message
news:b3sh6.1653$FU5....@ozemail.com.au...
> > You may get up to 8 kHz out of a 210 mm driver but I very much doubt
that
>> it
> > is without cone breakup - and so without some time smearing.
>
> No need to doubt it. Evidence by way of the cumulative spectral decay
> measurement is on our web site at www.vaf.com.au ...follow the links to
the
> DC-X then click on specifications...Check it out...it is very even and
very
> fast, and we use no electrical crossover on the woofer.
> Best regards
> Philip
>
>
VAF Research
looked
> at the spectral decay (waterfall) plots of the DCX on your website.
Hmmm, 12-15dB down in just 0.2mS across the entire range from 1KHz-20KHz
doesn't impress you? Curious.
> The plots show strong evidence of breakup in the 1-2 kHz region and again
in
> the 3-8kHz region where there appear to be resonances (ringing) that take
> nearly 2 ms to decay by -25dB. Assuming one is playing music at 85dB
these
> resonances would still be 60dB above the threshold of hearing and still
very
> audible.
Yes, after the remarkably fast and even 12-15dB drop in just 0.2mS the
retained energy at some frequencies is 25dB, or more, below the signal
within 2mS.
[snip]
> I suspect from my previous experience (I am a materials scientist as well
as
> a physicist) and from the above evidence that breakup of your cone is
> occurring quite early (around 1 kHz) but is relatively well controlled by
> the pads etc which I think you apply to the cones. Hence the good
linearity
> in frequency response, despite the resonances (I have seen some
> polypropylene cones giving similar results), which enables you to use no
> electrical crossover (though the work of Thiele and Small suggest
mechanical
> and electrical 'filters' are equivalent).
Things are not always as they seem....The DC-X is 'full' of mechanically
engineered technology that is not common. Again I point out the off axis
response which is nothing like what would normally be expected from such an
array....30deg shows an almost direct overlay with regard to the on axis
except for a few dB around 20KHz as is expected from a 25mm dome.
Rod Crawford
I have strong doubts about your interpretation because it seems to me one
can't have it both ways.
EITHER the cone acts like a perfect piston and so there will be no cone
breakup/ringing - but then there will be off axis response falloff with
frequency and angle as the waves from different parts of the cone inevitably
cancel when the cone diameter is less than about the note's wavelength.
OR one could try to overcome the latter by changing the phase at different
parts of the cone by, say, varying the speed of the waves through the cone.
But then the cone would not be rigid and would flex, with cone
breakup/ringing.
IN ANY CASE, changing the phase across the cone in such a way that the sound
waves emanating add exactly at all frequencies and at all angles seems to me
improbably difficult. IN ADDITION, getting anything like the correct speed
in the cone would be also be extremely difficult because the speed of sound
in solids is much greater than the speed of sound in air - and because the
speed would have to change across the cone because of the curved crossection
of the cone.
Cheers
Rod
(Dr) Rod Crawford
for Legend Acoustics
"Fast, open, Australian speakers"
www.legendspeakers.com.au
VAF Research <phi...@vaf.com.au> wrote in message
news:967ekf$519$1...@pinah.connect.com.au...
Rod Crawford
VAF Research <phi...@vaf.com.au> wrote in message
news:96a255$rff$1...@pinah.connect.com.au...
> > I'm sorry but I do still have very strong doubts, particularly having
> looked
> > at the spectral decay (waterfall) plots of the DCX on your website.
>
> Hmmm, 12-15dB down in just 0.2mS across the entire range from 1KHz-20KHz
> doesn't impress you? Curious.
** Not at all 'curious'. Even on my assumption of a relatively low
listening level of 85 dB, 12-15 dB down would still be a 70 - 73 dB level
which is certainly more than audible. I could have chosen a more extreme
(but not unusual) listening level of 95 dB, in which case 12 -15 dB down
would be 80 - 83 dB, but was more interested in establishing some scientific
understanding than scoring marketing points (I had enough of that at Linn to
last a lifetime)! Looked at a slightly different way, 12 -15 dB down would
correspond to a 'distortion' of more between 5 and 10%.
>
> > The plots show strong evidence of breakup in the 1-2 kHz region and
again
> in
> > the 3-8kHz region where there appear to be resonances (ringing) that
take
> > nearly 2 ms to decay by -25dB. Assuming one is playing music at 85dB
> these
> > resonances would still be 60dB above the threshold of hearing and still
> very
> > audible.
>
> Yes, after the remarkably fast and even 12-15dB drop in just 0.2mS the
> retained energy at some frequencies is 25dB, or more, below the signal
> within 2mS.
>
** The graphs show to me retained energy at the - 25 dB level (60dB for a
signal of 85 dB; 70dB for a signal of 95 dB) over a significant part of the
1 - 10 kHz region. Don't get me wrong, Phil, they are good - but not
perfect (again, I am more interested in the science, not the marketing
hype).
> [snip]
>
> > I suspect from my previous experience (I am a materials scientist as
well
> as
> > a physicist) and from the above evidence that breakup of your cone is
> > occurring quite early (around 1 kHz) but is relatively well controlled
by
> > the pads etc which I think you apply to the cones. Hence the good
> linearity
> > in frequency response, despite the resonances (I have seen some
> > polypropylene cones giving similar results), which enables you to use no
> > electrical crossover (though the work of Thiele and Small suggest
> mechanical
> > and electrical 'filters' are equivalent).
>
> Things are not always as they seem....The DC-X is 'full' of mechanically
> engineered technology that is not common. Again I point out the off axis
> response which is nothing like what would normally be expected from such
an
> array....30deg shows an almost direct overlay with regard to the on axis
> except for a few dB around 20KHz as is expected from a 25mm dome.
>
** See my comments on off axis in a reply below. I have no reason to doubt
your experimental results, Phil, but am a little skeptical of your
explanation/interpretation of them.
>
> Best regards
> Philip Vafiadis
> VAF Research Pty Ltd
> www.vaf.com.au
**Cheers
Rod
(Dr) Rod Crawford
D Phil(Oxon), BApplSc(Hons)
VAF Research
> signal of 85 dB; 70dB for a signal of 95 dB) over a significant part of
the
> 1 - 10 kHz region. Don't get me wrong, Phil, they are good - but not
> perfect (again, I am more interested in the science, not the marketing
> hype).
Rod, Thankyou for agreeing that the performance of the DC-X is good. Your
inference that I have presented marketing hype in this thread is 'a bit of a
stretch'. I understand your points on the audibility of stored energy, and
this is why we spend so much time documenting it and tracking it
down....**unlike** almost everyone else in this industry!....With respect
Rod, VAF is more open with quantified measured data than almost anyone in
this industry and **certainly** in this industry in Australia.
It seems to me your position is that distortion and stored energy is
audible, and you are inferring that as the DC-X is not perfect in this
regard
there is nothing special about them.
I don't think anyone here in this group (or anywhere else) has ever claimed
the DC-X to be perfect however I believe the regard they are held in at
their price point in is unprecedented in this newsgroup.
Criticising something for not being perfect does not advance the science you
claim to be interested in......I am curious...if the DC-X are nothing
special, what other speakers can you think of in the $1399-$1729 price range
(RTA to assembled) that offer a finer level of **Documented** performance.
Good frequency response linearity is one thing, achieving this at the same
time as getting flat phase is another thing altogether...throw in fast &
even decay and good off axis performance..... I think the list of other
contenders is going to be very short, but more probably non-existent.
VAF Research
> can't have it both ways.
You are mistaken, I don't want it both ways...*YOU* were claiming your cones
were stiff. I was just making the point that Aorogel cones could not be
pistonic to the frequencies you indicated given their frequency response. As
I am sure you are aware a linear response is not possible from a cone with
motion that is purely pistonic....this is why we do not use such drivers in
2 way designs. Using a stiff cone in a 2 way design is also problematic for
the reasons you state below....why do you chase this goal?
> EITHER the cone acts like a perfect piston and so there will be no cone
> breakup/ringing - but then there will be off axis response falloff with
> frequency and angle as the waves from different parts of the cone
inevitably
> cancel when the cone diameter is less than about the note's wavelength.
Yes, this is why our 2 way designs are NOT made this way. Why do you find it
desirable to chase this particular paradigm?
> OR one could try to overcome the latter by changing the phase at different
> parts of the cone by, say, varying the speed of the waves through the
cone.
> But then the cone would not be rigid and would flex, with cone
> breakup/ringing.
No, you are assuming too many things on the one hand, and trying to be
'black & white on the other.
Any driver that has a natively linear responce must 'de-couple' to some
extent. This goes for your Aerogel's too, they are not as natively linear as
ours, but they are far from pure pistons. For good micro dynamic resolution
the voice coil and inner cone must behave 'as one' though.
> IN ANY CASE, changing the phase across the cone in such a way that the
sound
> waves emanating add exactly at all frequencies and at all angles seems to
me
> improbably difficult. IN ADDITION, getting anything like the correct
speed
> in the cone would be also be extremely difficult because the speed of
sound
> in solids is much greater than the speed of sound in air - and because the
> speed would have to change across the cone because of the curved
crossection
> of the cone.
Yes, it was difficult...but the results have been worthwhile. BTW we did not
compensate for the curved cone as this relates to only a very small error
(aprox 1/10 wavelenghth at 8KHz) and optimmising the horn effect to suport
inner cone radiation was judged to be more beneficial. Developing the R&D
capabilities we have within VAF certainly has been helpfull here....most
companies that bother to make measurements are fooling themselves thinking
their measurements are valid even though they are made in uncontrolled
environments.
Rod Crawford
Again apologies in this reply. I will also try to reply to your specific
points below.
VAF Research <phi...@vaf.com.au> wrote in message
news:96chnb$ivn$1...@pinah.connect.com.au...
> > ** The graphs show to me retained energy at the - 25 dB level (60dB for
a
> > signal of 85 dB; 70dB for a signal of 95 dB) over a significant part of
> the
> > 1 - 10 kHz region. Don't get me wrong, Phil, they are good - but not
> > perfect (again, I am more interested in the science, not the marketing
> > hype).
>
> Rod, Thankyou for agreeing that the performance of the DC-X is good. Your
> inference that I have presented marketing hype in this thread is 'a bit of
a
> stretch'. I understand your points on the audibility of stored energy, and
> this is why we spend so much time documenting it and tracking it
> down....**unlike** almost everyone else in this industry!....With respect
> Rod, VAF is more open with quantified measured data than almost anyone in
> this industry and **certainly** in this industry in Australia.
I have no problems in admitting other companies' speakers, including your
DCX, are good - and that mine are not perfect! Indeed, one of the harder
battles I fought at Linn (and there were many) was to get them to admit this
and to buy other speakers for bench-marking and learning.
>
> It seems to me your position is that distortion and stored energy is
> audible, and you are inferring that as the DC-X is not perfect in this
> regard
> there is nothing special about them.
>
> I don't think anyone here in this group (or anywhere else) has ever
claimed
> the DC-X to be perfect however I believe the regard they are held in at
> their price point in is unprecedented in this newsgroup.
>
> Criticising something for not being perfect does not advance the science
you
> claim to be interested in......I am curious...if the DC-X are nothing
> special, what other speakers can you think of in the $1399-$1729 price
range
> (RTA to assembled) that offer a finer level of **Documented** performance.
> Good frequency response linearity is one thing, achieving this at the same
> time as getting flat phase is another thing altogether...throw in fast &
> even decay and good off axis performance..... I think the list of other
> contenders is going to be very short, but more probably non-existent.
I hope I was not critising your speakers for not being perfect - I was just
trying tease out what was scientific and what was marketing (explained in
more detail in another part of this thread). As I said in this newsgroup
some time ago, from what I heard and saw of VAF speakers at the Sydney hifi
show, they represent good design compromises at their price points. I
suspect that VAF's undoubted success is well deserved through following
marketing's '5Ps ' - performance, price, placement (distribution), packaging
of product and promotion - better than most. And long may it continue - I
would far prefer people to buy good Aussie products based on this than to
buy overseas ones based on reputation alone.
>
> Best regards
> Philip Vafiadis
> VAF Research Pty Ltd
> www.vaf.com.au
>
Cheers
Rod
(Dr) Rod Crawford
Rod Crawford
Sorry about the delay in this reply but I have been out of town for the past
couple of days. I will try to answer your specific points interspersed with
yours (which may get messy) but first some general points. I will try to
keep my comments objective. The main reason for keeping this thread running
(like you I have more than enough else to keep myself busy) has been trying
to tease out the scientific from the marketing. I had plenty of practice of
this at Linn eg "turntables can be engineered to sound different/better'
(scientific) from "there is a heirachy of hifi components with turntables at
the top" (marketing).
VAF Research <phi...@vaf.com.au> wrote in message
news:96cjpa$jkk$1...@pinah.connect.com.au...
> > I have strong doubts about your interpretation because it seems to me
one
> > can't have it both ways.
>
> You are mistaken, I don't want it both ways...*YOU* were claiming your
cones
> were stiff. I was just making the point that Aorogel cones could not be
> pistonic to the frequencies you indicated given their frequency response.
As
> I am sure you are aware a linear response is not possible from a cone with
> motion that is purely pistonic....this is why we do not use such drivers
in
> 2 way designs. Using a stiff cone in a 2 way design is also problematic
for
> the reasons you state below....why do you chase this goal?
Absolutely linear reponse ( of amplitude and so phase) is ONLY possible if
the driver motion is pistonic. By definition, if it is not purely pistonic,
there must be cone breakup and so resonance which must lead to some
peaks/troughs in the instantaneous frequency response (and so phase) and to
ringing with time. These latter can be reduced by damping but not
eliminated.
> > EITHER the cone acts like a perfect piston and so there will be no cone
> > breakup/ringing - but then there will be off axis response falloff with
> > frequency and angle as the waves from different parts of the cone
> inevitably
> > cancel when the cone diameter is less than about the note's wavelength.
>
> Yes, this is why our 2 way designs are NOT made this way. Why do you find
it
> desirable to chase this particular paradigm?
ALL serious speaker designers have their particular design priorities when
trying to optimise their compromises (caused by the laws of physics, state
of materials science, cost etc). You keep emphasising the importance of
phase which I guess must be important to you - to me it is of lower priority
at higher frequencies because I believe the ear is less sensitive to phase
at higher frequencies (for reasons, see earlier posts). One of my
priorities is the microdynamics of recordings - I like to be able to hear
the difference between performers. recording spaces etc (or at a gross
level, between Bach and Minogue to use the parody of an ealier post which
may have been too pythonesque). Hence our logo "fast, open (Australian)
sound". This means trying to reduce resonances (which smear the
microdynamics) incones, cabinets, internal cavities etc (our speakers also
contain lots of hidden engineering)! However, I am very aware of the
dangers of being too obsessed by one objective, having seen many speakers
spoiled by this, and so keep a close eye on other design parameters such as
frequency response, imaging etc (though the latter seems to follow from good
micodynamics and frequency response).
My gut feeling (coming from 5 of the 'best' years of my life studying the
mechanical properties of materials, largely using diffraction techniques) is
that the explanation of your experimental results via the speed of sound
does not seem plausible (to me), as I tried to explain in my post. However,
it would probably require another PhD of theory and experiment to try to
prove it!
> Best regards
> Philip Vafiadis
> VAF Research Pty Ltd
> www.vaf.com.au
>
Cheers
VAF Research
> (like you I have more than enough else to keep myself busy) has been
trying
> to tease out the scientific from the marketing.
[snip]
> My gut feeling (coming from 5 of the 'best' years of my life studying the
> mechanical properties of materials, largely using diffraction techniques)
is
> that the explanation of your experimental results via the speed of sound
> does not seem plausible (to me), as I tried to explain in my post.
However,
> it would probably require another PhD of theory and experiment to try to
> prove it!
Your preface stating that your goal is to seperate the science from the
marketing does not seem consistent with your conclusion...based on your 'gut
feel'.
You dismiss my reasonong based on your 'gut feel' however given the on *AND*
off axis frequency response, the almost perfect phase response of our DC-X,
and the use of 200mm woofers running full range to around 8Khz, can you
propose another theory to explain this measured data?
Again it is your inference that I take issue with.....that as it is
difficult and as you have not acheived it.... it is not possible.
Well, it was difficult.... I did acheive it.... and the results, measured
data and accolades speak for themselves.
Rod, I am not trying to score marketing points here....I have limited my
comments soley to the issues at hand and I expect you care about performance
of your loudspeakers, but it seems to me that you position is purely your
*opinion* and is not substantiated by any scientific methodology.
....half science + half guesswork = unreliable conclusions.
Patrick Scully
> Hi Phil
> snip <
>I suspect that VAF's undoubted success is well deserved through following
> marketing's '5Ps ' - performance, price, placement (distribution),
packaging
> of product and promotion - better than most.
Seeing that accuracy is being discussed here :-)) Lets get the marketing
right also. There are 4P's, Product, Place, Price and Promotion - Kotler
(1976). Latterly, certain academics have added a 5th P, for Positioning,
after Reis and Trout (1981). But as Positioning is in fact a Promotion
Strategy, there are still only 4P's involved in the Marketing Mix.
Get these right, and follow what is observed to work, and your business will
thrive and grow!
In the interests of accuracy:-))
--
regards
Patric Scully (LLB., BSc. Elec. Eng. B. Mark., MBA., PhD.)
The Sound Man
Rod Crawford
> > The main reason for keeping this thread running
> > (like you I have more than enough else to keep myself busy) has been
> trying
> > to tease out the scientific from the marketing.
>
> [snip]
>
> > My gut feeling (coming from 5 of the 'best' years of my life studying
the
> > mechanical properties of materials, largely using diffraction
techniques)
> is
> > that the explanation of your experimental results via the speed of sound
> > does not seem plausible (to me), as I tried to explain in my post.
> However,
> > it would probably require another PhD of theory and experiment to try to
> > prove it!
>
> marketing does not seem consistent with your conclusion...based on your
'gut
> feel'.
>
> You dismiss my reasonong based on your 'gut feel' however given the on
*AND*
> off axis frequency response, the almost perfect phase response of our
DC-X,
> and the use of 200mm woofers running full range to around 8Khz, can you
> propose another theory to explain this measured data?
>
> Again it is your inference that I take issue with.....that as it is
> difficult and as you have not acheived it.... it is not possible.
>
> Well, it was difficult.... I did acheive it.... and the results, measured
> data and accolades speak for themselves.
>
> Rod, I am not trying to score marketing points here....I have limited my
> comments soley to the issues at hand and I expect you care about
performance
> of your loudspeakers, but it seems to me that you position is purely your
> *opinion* and is not substantiated by any scientific methodology.
>
> ....half science + half guesswork = unreliable conclusions.
>
> Best regards
> Philip Vafiadis
> VAF Research Pty Ltd
> www.vaf.com.au
>
>
>
methodology (it has deviated enough from its original starting point already
and is probably well into diminishing, if not negative, returns) but much of
science starts with a gut feel (based on past experience) and then proceeds
to try to prove whether it true or not true. One of the differences with
marketing is that assumptions, doubts and falseability are inherent in the
process - but are made upfront/explicit. Theory can help us fumble our way
forward into the unknown. To paraphrase physics Nobel laureate Richard
Fyneman - one of the burdens of being with a scientist is continual
questioning and so living with perpetual uncertainty. This usually
contrasts with marketing which has to project certainty and confidence to
potential customers. In this thread, as a scientist I naturally expressed
myself using terms like I suspect, would require more evidence to prove my
case etc. I could have used the more conventional (for this newsgroup) IMO
or IMHO etc but as a scientist I assume this is implicit in everything we
say (perhaps this was a mistake). And I did not mean to imply that it was
impossible to do difficult things.
Regarding your more specific point(s), your well deserved accolades etc may
have been for your results, rather for your theory/explanation. Very few
customers would or should buy speakers purely on the basis of theory - and
very few reviewers are scientists. Theory is largely there to help
designers fumble their way forward. If I had to GUESS (based on my previous
theoretical/practical experience and from the evidence I have seen so far)
what would be an alternative explanation, it would
be that the 200 mm cone would be well into breakup mode by 2 kHz, where
sound
's wavelength in air becomes the same order of magnitude as the cone
diameter and so beaming should start to set in. However, as frequency
increases, increasing cone breakup means varying parts of the cone have with
little coherent phase relationship between them and so little phase related
reinforcement and destruction with angle and frequency. This would give
good off-axis power performance and constant (averaged) phase; but it would
lead to some smearing in time due to the cone breakup/ringing, though the
latter could be reduced with heavy cone damping (as I think you use on the
DCX cones). For me (IMHO) this is more plausible (and as useful to me) as
your velocity theory - but as I stated quite explicitly, I would have to do
too much more work make the answer more certain one way or the other (to
me). If
you find your velocity theory more plausible/useful to you, that is fine by
me -
and others in the newsgroup (if anyone else is still reading) will have to
make up their own mind what is useful to them. Science is essentially
democratic.
Cheers
Rod
(Dr) Rod Crawford )
Rod Crawford
Thanks for correcting me, Patrick. Some marketing 'gurus' have extended
them to "7 Ps" - but I can't remember for sure what the others were (perhaps
one of them was "packaging" which why I was confused)!
Cheers
Rod
(Dr) Rod Crawford
DPhil(Oxon) MBA(AGSM) BAppSc(Hons)
for Legend Acoustics
"Fast, open, Australian speakers"
www.legendspeakers.com.au
Patrick Scully <soun...@starwon.com.au> wrote in message
news:3a8d39a1$1...@usenet.per.paradox.net.au...
Rod Crawford
reading your message. Sorry. Consulting my remaining marketing notes from
the AGSM (1991-2) suggests that Koetler's original 4Ps (product, price,
place and promotion) were expanded to 5Ps to include packaging (which is
probably not included in the other 4). I still have it in the back of my
mind that some later authors extended the list still further but cannot find
a reference to these in my notes (many of which were thrown out when moving
to Canberra from Sydney). However, despite some dispute about the details,
your comments reinforce the point I was originally trying to make - market
success is rarely due to product performance alone, but equally due to a
range of other factors (which I think VAF do very well).
Cheers
Rod
Rod Crawford <leg...@canberra.teknet.net.au> wrote in message
news:8mij6.14$o1....@nsw.nnrp.telstra.net...
Geoff
> them to "7 Ps" - but I can't remember for sure what the others were
(perhaps
> one of them was "packaging" which why I was confused)!
That's marketing gurus for you. Any strategy with SEVEN P's has gotta be
better than one with only four, right? I mean seven! that's almost twice as
many :)
Geoff
> Phil, I don't want to extend this thread to a discussion of scientific
> methodology (it has deviated enough from its original starting point
already
> and is probably well into diminishing, if not negative, returns) but much
of
So you want to argue using 'science' but not talk about ways to verify that
you're right? Any science theory must have a way of being verified, or you
might as well keep on standing right where you are because as far as you can
see the earth is flat and if you keep walking you're going to fall off the
edge.
> forward into the unknown. To paraphrase physics Nobel laureate Richard
> Fyneman - one of the burdens of being with a scientist is continual
> questioning and so living with perpetual uncertainty. This usually
To be pedantic: it's Feynman. :)
I think it's more realistic living in an uncertain world. It's teenagers
that think "I can definitely drive at 100km/h around a bend in the wet" and
actually they can't, but they believed it was true so for them it was
certain. Living in a world of certainty is living with your head in the
sand. Among other things it's boring. I'm not saying Feynman is wrong, but
somebody as brilliant as him would go utterly insane if they went into
marketing.
> contrasts with marketing which has to project certainty and confidence to
> potential customers. In this thread, as a scientist I naturally
expressed
Yes, marketing is full of confidence and positive words. But that's because
they're trying to sell something. You don't sell a sony receiver by putting
the engineer in front of the customer who says "Yeah, this amp does 100W per
channel RMS. However, that's only if you've got one speaker attached. The
power supply is actually nowhere near powerful enough to supply 100W to all
5 channels". Customer's going to go what the hell do I want that for?? 20W
RMS per channel? how lame!
> Regarding your more specific point(s), your well deserved accolades etc
may
> have been for your results, rather for your theory/explanation. Very few
I believe he's selling speakers, not teaching people how they should be
making them. VAF's primary focus is on building a great set of speakers and
selling them to customers who appreciate the quality. I think you're being
a bit unreasonable expecting so much debate from Phil here, he has a *MUCH*
more visible presence than the designers of most audio equipment and is
pretty open and honest when it comes to discussing his products. There's
certainly a hell of a lot more information than most speakers provide. I've
never seen a spectral decay graph being provided before.
Of course there will be design compromises. Is it better to produce a 5"
woofer and 1" tweeter, and then do what you can to reduce cone breakup and
all that? Or is it better to have a 6" woofer, a 4" woofer, a 2" dome and a
1" tweeter? I'd hazard a guess it's easier to design a 2-way system and work
on the design of the cones than have to worry about a 4 way crossover
blending smoothly together.
The main point to consider is that to build speakers to a price you have to
make design compromises. Has Phil chosen sensible compromises? Has he done
the best he can given the price?
As a side note, there's no reason why VAF should have to justify itself.
The product is there, if you want it you can choose to buy it. It's totally
the consumer's choice. Likewise with the Dynalab boys, if they want to sell
$50 speakers for $300 then good luck to them. The only thing I disapprove
of is that they lie by telling you that the speakers cost them a thousand.
If they just said "hey I've got some good speakers, I need to get rid of
them, you can have them for $300". Sure, the "good" is a bit of a lie but
"good" is a very subjective word. If people are dumb enough to fall for it
then they'll learn a hard lesson.
Note that this is all said in response to the most recent bits of debate.
I've got no clue what the original argument about the Kantus not having much
treble was all about... my newsreader doesn't go back that far :)
Geoff
Dale
make up their own mind what is useful to them. Science is >essentially
democratic.
it's refreshing to see differences discussed technically, and for people
like me, educationally. to me this whole discussion gives me (the consumer)
more confidence in trusting the products from both of you, as your behaviour
has come across as grounded professional and respectful.
for someone with a hobby in audio it has also been hugely informing, thank
you both for not going private.
dale
Patrick Scully
> Patrick, the below was written very quickly while I was still on-line
after
> reading your message. Sorry.
No need to apologise, while my response WAS serious also it was meant to be
somewhat humorous. Seeing as you filled in your slate of designatory letters
:-)) I guess you did catch the humour.
I'll raise you one Grad. Dip. Ed. & a Dip. Assessment and Training Systems,
your call:-))
> Consulting my remaining marketing notes from
> the AGSM (1991-2) suggests that Koetler's original 4Ps (product, price,
> place and promotion) were expanded to 5Ps to include packaging (which is
> probably not included in the other 4).
Didn't know that, since coming to Aus in 88 (also when I completed the PhD)
I have worked with SME's which I have found really don't have very much use
for high-end strategic marketing theory and practice. IME they usually don't
really have the resources - human, physical AND financial - to implement the
solutions indicated by such an approach.
But with respect to packaging, this is an element that straddles all four of
the P's - Promotion because how the goods/services are presented is a
critical element in the promotion mix; Place because channel of distribution
decisions impinge on the efficacy of packaging, as a materials scientist you
may have come across this in the past; Product because one of the functions
of packaging is to preserve the integrity of the product while in transit to
the end user; and finally Price because packaging is also a cost as well as
an investment in marketing, product integrity, etc. So I would resist any
marketing guru's attempts to augment the fundamentals of the marketing mix -
perhaps a I'm being a bit pedantic, but I am also an engineer who was
trained not to meddle with or to try and fix that which is not broken :-))
> I still have it in the back of my
> mind that some later authors extended the list still further but cannot
find
> a reference to these in my notes (many of which were thrown out when
moving
> to Canberra from Sydney).
Yes, as alluded to above. It is an unfortunate trait of academics in the
Humanities (at least some of them) to always be meddling around with the
paradigm, any paradigm. As you probably know, they don't actually get their
kudos from anything as mundane as teaching :-)) No, they must research,
research, research ... and publish, publish, publish!
This of course is regardless of any real need in many cases. Also I have to
comment (well, not really, but I will anyway) about the different academic
regimes that one finds in Australia compared to other locations at lease in
management, marketing, etc. I have noticed a serious propensity among local
practitioners not to be satisfied with good work done over seas, such that
it must be redone locally by them, and in many cases not adding anything to
the paradigm and even getting very close to plagiarism.
A good recent example of (nearly) this is the use of work by Henry Minceberg
in a very non-scholarly way, and simply mention him in the text as "An
American academic ..." I won't go further with this, I brought my LLB up to
scratch with Australian Law, particularly the laws governing libel ...
> However, despite some dispute about the details,
> your comments reinforce the point I was originally trying to make - market
> success is rarely due to product performance alone, but equally due to a
> range of other factors (which I think VAF do very well).
Yes, despite the humourous approach, it was my intention to support rather
than sledge! But I would go further than you, IME I have NEVER come across a
successful product where the marketing was not done properly. It is the
critical factor in success. But by marketing I do NOT mean the (local)
limited context that I find, i.e., marketing = advertising, rather in the
context that Marketing is a total approach to running a business. This view
really is the foundation of the Marketing Concept.
Marketing is about behaviour, human behaviour, and how one might stimulate
such behaviour in one's favour. In other words, marketing depends HEAVILY on
Psychology, in particular all of the work on perception. A recent thread on
centre speakers almost provoked me to get my feet wet here for 2001, based
on some behavioural research we did in Europe over four months late last
year. But some of the die-hards that post hereabouts would have fits of
insecurity where what we found to be placed in the public domain.
But if you or Phil ARE interested in the broad outcomes, and would like to
replicate the research, please let me know.
But I don't believe that you will want to make public what you find. The
people with whom I did the work - a joint venture partner in a manufacturing
project in Europe - made me promise not to disclose in public what we found.
But for a student of Psychology, particularly in the domain of
psycho-accoustics, there were no surprises, and the outcomes where totally
predictable.
>
> Cheers
> Rod
>
--
regards
Patric Scully
The Sound Man
Rod Crawford
Patrick Scully <soun...@starwon.com.au> wrote in message
news:3a8e...@usenet.per.paradox.net.au...
> "Rod Crawford" <leg...@canberra.teknet.net.au> wrote in message
> news:Vdkj6.23$o1....@nsw.nnrp.telstra.net...
> > Patrick, the below was written very quickly while I was still on-line
> after
> > reading your message. Sorry.
>
> No need to apologise, while my response WAS serious also it was meant to
be
> somewhat humorous. Seeing as you filled in your slate of designatory
letters
> :-)) I guess you did catch the humour.
>
> I'll raise you one Grad. Dip. Ed. & a Dip. Assessment and Training
Systems,
> your call:-))
>
** I could have thrown in Dip Ed but still would have been outbid (and it
is all irrelevant anyway!!
** It may also indicate that any classification scheme is somewhat
arbitary - and so choice has to be made on a cost benefit/approach.
Certainly adding more classes has costs - most people cannot remember more
than 4 or five items(as I think I have shown)! I am not enough of a
marketing 'expert' to comment on whether Koetler's classification is the
best but it certainly seems to have withstood the test of time.
** You may be being a bit hard on Australians - it is a trait of many
academics! (and, despite having spent too many years in the mother country,
I am still fiercely Oz)!!
** Many thanks, Patric, I would be very interested in the broad outcomes.
Unfortunately I do not have time at the moment to replicate the research - I
really struggle to find time continue these posts (most, like this, are
written around 6 am, before I start work).
Cheers
Rod
Rod Crawford
Geoff <spamif...@cyberjunkie.com> wrote in message
news:jslj6.8891$pG5....@news1.rdc1.nsw.optushome.com.au...
Hi Goeff
I agree with what you say - but, having seen only part of the thread, you
missed much of the context of my comments.
Of course science must have a way trying to verify what it finds - but this
is itself a difficult topic (as anyone who has studied the philosophy of
science will know) . I was at this point in the thread just trying to make
the point (with which you seem to agree) that science and advertising have
different orientations/attitudes as starting points.
As I implied in my last post, I don't think VAF needs to justify its theory
to its customers - they should buy on results. Theory is largely for
designers (amateur or commercial) who are (hopefully) trying to improve
things (push back the frontier). But Phil quoted his theory earlier in this
thread - and as a (commercial) designer I expressed my doubt, in the trying
to further understanding. My conclusion (and others may differ) is that I
still have strong doubts, but do not have enough evidence (theoretical or
experimental) one way or the other at this time.
Cheers
Rod
(Dr) Rod Crawford
for Legend Acoustics
"Fast, open, Australian speakers"
www.legendspeakers.com.au
Geoff
Geoff
> missed much of the context of my comments.
yep
> science will know) . I was at this point in the thread just trying to
make
> the point (with which you seem to agree) that science and advertising have
> different orientations/attitudes as starting points.
totally...
> As I implied in my last post, I don't think VAF needs to justify its
theory
> to its customers - they should buy on results. Theory is largely for
I think customers should tend to focus on the sound, using their ears.
However it comes across well if you grill a speaker (no that's not a pun)
manufacturer and they really know what they're talking about from a
technical point of view as well. It shows that they approach their work
from two directions, getting the best sound as well as following some solid
theory.
> designers (amateur or commercial) who are (hopefully) trying to improve
> things (push back the frontier). But Phil quoted his theory earlier in
this
> thread - and as a (commercial) designer I expressed my doubt, in the
trying
> to further understanding. My conclusion (and others may differ) is that I
> still have strong doubts, but do not have enough evidence (theoretical or
> experimental) one way or the other at this time.
Well even if the theory isn't quite correct, do the conclusions lead to
better sound? If so, then I'm half happy :)
Of course a good theoretical debate is also good. The other half comes if
the theory was correct after all.
Geoff
Patrick Scully
--
regards
Patric Scully
The Sound Man
"Rod Crawford" <leg...@canberra.teknet.net.au> wrote in message
news:3qWj6.6$Cu....@nsw.nnrp.telstra.net...
>
> snip <
>
>
> ** I could have thrown in Dip Ed but still would have been outbid (and
it
> is all irrelevant anyway!!
That was my point :-))
>
> > perhaps a I'm being a bit pedantic, but I am also an engineer who was
> > trained not to meddle with or to try and fix that which is not broken
:-))
>
>
>
> ** It may also indicate that any classification scheme is somewhat
> arbitary - and so choice has to be made on a cost benefit/approach.
True. IME, the P's are best viewed as a set of sets, rather as a systems
than individual components.
> I am not enough of a marketing 'expert' to comment on
> whether Koetler's classification is the
> best but it certainly seems to have withstood the test of time.
Agreed.
>
>
> ** You may be being a bit hard on Australians - it is a trait of many
> academics!
True
(and, despite having spent too many years in the mother country,
> I am still fiercely Oz)!!
As you should be!!
>
> >
> > But if you or Phil ARE interested in the broad outcomes, and would like
to
> > replicate the research, please let me know.
> >
>
>
>
> ** Many thanks, Patric, I would be very interested in the broad outcomes.
> Unfortunately I do not have time at the moment to replicate the research -
I
> really struggle to find time continue these posts (most, like this, are
> written around 6 am, before I start work).
Point taken, I will pass them on by email later in the week.
>
> Cheers
> Rod