Howard Ferstler wrote:
John Atkinson wrote:
Howard Ferstler wrote:
2) Because conventional, flat-panel systems also expand and
contract in size, compared to what the curved ML panel does,
they probably have horizontal dispersion nearly as good as
the curved versions.

Not in my experience. If you look at my measurements of the
Innersound Eros' horizontal dispersion -- see
http://stereophile.com/loudspeakerre...19/index6.html --
then look at my measurements of the similarly proportioned
panel of the MartinLogan Prodigy -- see
http://www.stereophile.com//loudspea...90/index5.html --
you can see that the Prodigy's curved panel does indeed offer
wider treble dispersion.

But still not particularly wide, compared to what good
dynamic speakers with smallish midrange (2 to 4 inch) and
tweeter (3/4 to one inch) drivers can do.

Did you look at these dispersion graphs, Mr. Ferstler? Yes,
the flat panel of the Innersound speaker has the very
restricted treble radiation pattern to which you were
referring but the MartinLogan doesn't, thus proving your
first statement above incorrect in all aspects.

compare the radiation patterns of the two electrostatic
speakers I referenced above. Whether it is due to the ML's
curved diaphragm or to some other factor, their panel does
indeed offer quite good lateral dispersion.

Out to how many degrees off axis?

How hard is it for you to click on a link, Mr. Ferstler?
If you actually looked at the dispersion graphs that I
published you would find the answer to your question.

Needless to say, my Allison IC-20 systems satisfy most
wide-dispersion requirements.

Except that these speakers do not have wide dispersion, Mr.
Ferstler, nor have you provided any measurements that support
this claim.

Do not have wide dispersion? Give me a break. Do not posture
about this, John. You know as well as I that whatever one
may think of the Allison designs, poor dispersion is not one
of their characteristics.

I am not "posturing," whatever you mean by that word, Mr.
Ferstler. You have written at length about the supposed
wide dispersion of the Allison tweeter, but it appears to be
no better than any other 3/4" unit in this respect. I note
also that you have also _not_ measured its dispersion. In
addition, 1) it is naive for you to assume that the drive-unit's
dispersion is not modified by the speaker baffle and 2) no
matter how wide the tweeter's dispersion, this will be
radically altered by the use of _two_ of them. Two laterally
spaced tweeters offer a narrower horizontal radiation pattern
than one alone.

The original reviews of the IC-20 systems by both High
Fidelity Magazine and Stereo Review commented upon their
ultra-wide dispersion.

But what measurements did those magazines publish to
support that contention? And how where those measurements
performed? Perhaps I am mistaken, but I can't remember
the late Julian Hirsch performing either polar plots or
the waterfall dispersion plots that I perform in Stereo
Review. And again if I remember correctly, High Fidelity only
performed sound _power_ measurements.

Even if the systems had only one forward-facing panel they
would have those Allison drivers dispersing widely clear out
to 90 degrees off axis.

But without measured support for this statement, you have
no basis to make it, unless you label it as being your _opinion_.

However, they have dual panels, each angled out 45 degrees
from dead ahead, meaning that they have extremely wide
dispersion to each side and out to 135 degrees off axis.

No, this results in _narrower_ dispersion on the primary
frontal axis, with complex lobing apparent.

John Atkinson
Editor, Stereophile

wrote:
wrote:

snipped

Stephen asked:

"Curvilinear"? Isn't that ML's way of trying to be
more
Ferstler-approved by diddling the dispersion?

Howard ferstler answered:

Actually, unless the diaphragm is changing size as it
moves
back and forth, the curved shape will not allow for
any
better dispersion than what we would get with a flat
diaphragm.

Scott Wheeler shot from the hip:


Guess again dimbulb.


And now, here's Scott Wheeler's 'final answer':


Still don't get it do you? I guess I have to spell it out for you.
Howie is bright enough to know the diaphrams are fixed at the
parimeter. He questions whether or not the CLS technology will
really
work because to do so the diaphram would have to change size (flex)
but
he's not bright enough to figure out that the damned thing wouldn't
make any ****ing sound at all if it weren't flexing to begin with!
So
there. You are all idiots. Get a life. It would be about the same
to
question whether automobile technology really works because the
wheels
would have to turn for the car to go anywhere.


Here's a news flash: "flexing" and "changing size" *are not* the same
thing. Go read what Howard said. Howard was addressing the issue of
whether or not M-L's "CLS technology" affects the (horizontal)
dispersion v. a (conventional) flat diaphragm. Care to address *that*
issue with facts?




And all this time I thought you were just being a prick. You *really
are* this stupid. I suggest you stick with what you do best, finding
spelling mistakes, being an asshole and spounging off mom and dad. You
may want to quietly review your grade school geometry in your (chuckle)
spare time. Here is one last hint for you, good luck with understanding
it. When talking about a stretched diaphram like the ones in the CLSs
flexing and changing size/stretching *are* the same thing. As for how
all this affects the dispersion of the CLS speakers I suggest you
consider what happens to a diaphram that is fixed on it's parimeter
when it moves closer to the stator that is infront of it. Again, you
may want to review your grade school geometry before working on this
simple concept. Have fun figuring things out.



Scott Wheeler

In article ,
"Arny Krueger" wrote:

MINe 109 wrote:
In article ,
"Arny Krueger" wrote:

MINe 109 wrote:
In article ,
Howard Ferstler wrote:

That leaves the pipe organ. Now, I have a lot of pipe-organ
recordings and some do indeed, go down to below 25 or 30 Hz,
or even below 20 Hz. I have a couple that are strong to
16-18 Hz. However, while you may enjoy some organ concerts
here and there, my guess is that only rarely have those
organs hit the very bottom. They would not do that without
32-foot pipes in any case, and my guess is that the organ at
your establishment does not have those.

These days a lot of organs don't have 32 foot pipes, they have
electronics and subwoofers instead.

Even pipe organs sneak 'em in.

Exactly.

So, Stephen, I continue to believe that you have yet to hear
really deep bass from an audio system. Man, you do not know
what you are missing.

Given that Stephen is still flogging the dead vinyl horse, he's got
a
lot of incentive to have a system with weak basss. Deep bass and
vinyl are hard to mix. Furthermore, a lot of vinyl has the deep
bass
removed or mono-ized in the interest of having a recording that
people could actually play. On the best day of vinyl's life, deep
bass meant short sides.

Dude, the cd player's hooked up to the same system.

So what?

So my choice of a speaker with relatively limited bass is unrelated to
my including a turntable in my system.

Stephen

On 4/13/05 9:33 PM, in article , "Howard
Ferstler" wrote:

John Stone wrote:

On 4/13/05 5:07 PM, in article , "Howard
Ferstler" wrote:

It is. The tweeter behaves similarly to a pulsating
hemisphere of very small size.

Howard, what proof is there of this "pulsating sphere" theory?

Hi, John. I continue to be amazed at how often I can mention
somebody here or mention a topic that is close to the heart
of such individuals and suddenly I read a post by them
discussing (or contesting) my views. I wonder just how many
lurkers we have out there in RAO land.

Wouldn't who they are be even more interesting?

Note that I said "pulsating hemisphere" and not "pulsating
sphere." If you are going to take jabs at me, at least get
your quotes correct. In any case, there is no "proof," per
se, other than two things:

1. Allison's description of how the driver worked, which
almost by definition proves the point.

2. Assorted product reviews over the years that lauded the
dispersion qualities of the tweeter.

How does this constitute any proof? It works that way because Allison says
it does? It works that way because it makes sound? It works that way because
reviewers say so? It works that way because it has wide dispersion, even
though any 1/2" dome tweeter without a "pulsating hemisphere" also has wide
dispersion? You're arguing in circles here.

Has anyone
ever done a laser holography analysis of this tweeter to see if it actually
behaves this way at operating frequencies? From what I see, the Allison
tweeter in the high frequencies has dispersion characteristics that are
pretty consistent with a standard 1/2" dome.

Yep. However, it has power handling that is superior to a
1/2-inch dome. As best I can tell, nobody has done a laser
holography analysis of the tweeter. It does disperse widely,
however, doesn't it John?
Yes, we've already established that it disperses similarly to a 1/2" dome
tweeter, because in essence, that's what it is-albeit with a wide paper
surround.

How does it compare with the best
3/4-inch drivers made by your company, particularly above 8
kHz and beyond 60 degrees off axis?
Howard, tweeters are not all about output above 8kHz beyond 60 degrees off
axis. If that was so, then they would only be used and measured that way. So
lets take a full comparison. Our best 3/4" drivers are at least 4dB more
sensitive, they are flat in the low end, and will still handle considerably
more power than the Allison. Above 8 kHz, beyond 60degrees, the Allison will
have more "acoustic energy". This is defined by their smaller radiating
diameter. However, such energy shows no resemblance to a smooth response
curve, because diffraction effects at these angles will dominate the output,
and increasingly so with greater angle and frequency. So you get extremely
choppy output at a level higher than what we get from a 19mm dome. Is that
wide angle energy valuable at any cost? To you it seems paramount. To any
designer I know, it isn't even an issue. In fact, some prominent designers I
know would say it isn't even desirable.
This makes perfect sense given
the diameter of the voice coil, and the fact that high frequency radiation
in "soft diaphragm" tweeters is largely concentrated to the area closest to
the voice coil.

Sure. In any case, the tweeter has exemplary dispersion.
Perhaps the most notable thing about this is that the design
goes back three decades. It has taken those other companies
a long time to catch up, and for that matter, many still
have not caught up.

At least on one point we can agree, the design was interesting and
innovative 30 years ago. But time doesn't stand still and neither does
technology. By today's standards, does it do anything else "exemplary"
besides dispersion?
Linearity?
Sensitivity?
Power handling?
Distortion?




If shaping the Allison's diaphragm improves its dispersion, then
the same mechanism works for MartinLogan.

The ML device is much larger in size than the Allison unit.
Actually, the central dome of the Allison is only 1/2 inch
across, which makes it inherently better at dispersing sound
than any large diaphragm, even one that expands and
contracts as a partial cylinder.

I find it ludicrous to compare the 2 given that they operate on completely
different principles and over very different frequency ranges.

Well, the Allison tweeter either operates above 2 kHz
(two-way version, ferrofluid cooled) or above 3750 Hz
(three-way version, silicone grease cooled), whereas the ML
panel operates over a much broader range. However, above 2
kHz or 3750 Hz they are on a level playing field and they
can most certainly be compared. So, within the upper
midrange and treble ranges, we can compare fairly.
Please Howard, other than the fact that they are both transducers, they are
in no way comparable. One is a dipole the other a monopole, one
electrostatic, the other dynamic, one a line source, the other a point
source. If you want to compare apples to oranges just to make the point they
are different, then be my guest. Seems like a useless exercise to me.



The Allison tweeter has a
rather large surround, making the overall diameter about one
inch, and that surround moves in a somewhat radial manner,
which works with the small central diaphragm to disperse
sound nicely, while at the same time allowing the whole unit
do have power handling and power output approaching what we
normally have with conventional one-inch domes.

The "surround" as you call it is basically a small inverted paper cone. This
area of the driver will have little acoustic contribution to the upper
frequencies.

It moves radially and not just back and forth in parallel
with the dome section, and does indeed have an acoustic
contribution to the upper frequencies, simply by virtue of
its angular radiation.
Again, proof that it works this way? The fact that the tweeter produces
output does not confirm how it produces output. We both agreed that the
dispersion characteristics at high frequencies were a function of the small
diameter voice coil and consequently the small radiating area at high
frequencies. What then is the advantage of also having hf radiation off the
wide surround? This would mean that the effective radiating diameter at
those frequencies would be larger, and this would, by definition, work
against the wide dispersion, not for it. You can't have it both ways.

It also allows the driver to work
down to a lower frequency than what we would have with a
straightforward 1/2-inch dome.

Ok, Howard, now you're backtracking. Previously you said:
The Allison tweeter has a
rather large surround, making the overall diameter about one
inch, and that surround moves in a somewhat radial manner,
which works with the small central diaphragm to disperse
sound nicely, while at the same time allowing the whole unit
do have power handling and power output approaching what we
normally have with conventional one-inch domes.
That's what I disagreed with. I never brought up how it does against other
half inch domes. I don't even think half inch domes existed back then.
What I'm saying is that it doesn't come close to the low frequency
capability of a one inch dome nor does it have the sensitivity or power
handling of a one inch dome, even taking the power response at high
frequencies into account. It drops like a rock below 2kHz where 1 inchers
can still be flat nearly one octave lower. Realistically such a tweeter
shouldn't be used at a crossover frequency much lower than 3khz,even with a
fairly steep slope. A 1" dome can be crossed much lower.

It is clear from the large bump in the frequency response below
5kHz that the cone portion contributes most heavily to the tweeter's output
in this range.

Fine. So what? This allows it to disperse as well as a 1/2
incher, while at the same time being able to go down much
lower in frequency than a 1/2 incher. Note that the Allison
tweeter is a dedicated design that was built to work with a
specific crossover network designed by Allison. The "large
bump" in frequency response below 5 kHz was compensated for
by the dedicated crossover.

Yes, but the fact is that any transducer designer would prefer linear
response over non linear. The fact that the crossover has to compensate
doesn't mean that such response is preferable. BTW, in case you still
believe otherwise,virtually ALL speakers today have "dedicated crossovers"


Yep, Allison designed the
crossover and driver to work together and he did not have to
purchase OEM drivers and then build a crossover to
compensate for someone else's driver-design approach.

No, but he had to build one to compensate for his own driver design
approach. And regardless of what you say, a flat response in a transducer is
preferable to a non flat response. In this respect the Allison tweeter IS
inferior to others. No one said it can't be corrected for, but I suspect
even he would have preferred if the tweeter response was flat on its own.


As for power handling and output comparable to a 1"dome, I
disagree. No 1/2" voice coil is going to have anywhere near the power
handling of a 1" coil, especially with modern high temp wire on
aluminum formers, which is what is found in quality modern dome tweeters.

Well, the fact is that it can play more than loud enough to
satisfy typical listeners. Assorted reviewers of even those
systems that employed only one tweeter and one midrange will
validate that claim.
Please. As if "reviewers" were the last word on evaluating speaker
performance.


In addition, Allison was pretty
specific in outlining the power-handling qualities of that
tweeter in terms of power vs time (and the midrange and the
woofer) when all of them were installed in his systems. How
many other companies did (or do now) that sort of thing,
John? Allison was anything but vague about the performance
of his drivers.
I would say this was important for him to do, given that the tweeters were
relatively fragile by comparison. Didn't he have to build some kind of
protection into the crossover? If you have a lot of "headroom" in your
design, you don't have to be so specific, because the tweeter will be robust
enough to hold up under extreme circumstances. This is largely the case
today. We offer plenty of documentation regarding power handling of our
drivers based on various DIN specs. How the OEM's use that info and do their
own power testing is up to them.


And unlike many other "speaker" companies, Allison took his
design goals seriously enough to make his own drivers,
instead of purchasing them from companies like yours.
My company was not selling drivers in the OEM market when he designed that
tweeter. But my company has since done plenty to advance the art for the
speaker industry as a whole. What's wrong with that?

The overall sensitivity of the Allison tweeter when measured on axis and
normalized for flat response is pretty low: about at 1 meter.

On axis. What you are forgetting is the wide-anglular
response of the tweeter. Yes, on axis it seems output
limited. But because its strong off-axis response would be
reflected from room boundaries, its practical efficiency in
typical listening rooms was quite high. Surely, we have to
realize that one-meter, on-axis measurements of driver
efficiency will be misleading if we are comparing a
wide-dispersion driver to one that is more narrow in
dispersion.

But how do we reconcile this to designing a speaker system with measured
sensitivity greater than 85dB? Are you saying that the on axis response
should be rolled off? Look, regardless of what it throws off axis, you
still need linear on axis response too. You can't just dismiss it as
unimportant because the dispersion is wide. Besides, the Allison's off axis
dispersion advantage only applies to frequencies around 10kHz and above. You
still have to deal with the sensitivity issue in the lower end of the
operating range where you cross over from the woofer or mid. And for flat
response on axis, you will be stuck with the tweeter's on axis sensitivity.
I know of no contemporary designer that would sacrifice the on axis response
just for the sake of wide dispersion.

Compare that to most good 1" domes with 90dB or better sensitivity and near
ruler flat response with no eq .

So, you are saying that sensitivity is a factor in driver
accuracy or power handling? Well, I suppose the latter is a
viable approach, if we ignore the wide-angular response of
the tweeter, which makes on-axis efficiency measurements
misleading.

Yes, Howard, sensitivity is a big factor. Measure the steady state response
of an Allison tweeter after running it near its maximum for a period of time
and you'll see significant shifts in response and a drop in sensitivity.
Power compression is a real issue that gets worse with temperature. And
lower sensitivity tweeters put more energy into heat than higher sensitivity
ones. This is why speaker designers keep placing more and more demands on us
for higher sensitivity. Thankfully there are new materials and technology
that really can boost sensitivity. For example, neodymium, which didn't even
exist for driver use in the 70's.

The bottom line, however, is how well the tweeter holds up
in use, and with the Allison models that had even one of
them the output abilities were more than adequate.
If these tweeters are so "adequate", why do your IC20 systems need 4 of
them? And what are the acoustical compromises of having them spaced like
that?

Indeed,
when Dick Heyser reviewed the original Allison Model One for
Audio Magazine years ago he lauded the power handling and
maximum-output capabilities of the system. Note that Heyser
was a pinpoint imaging enthusiast, so he did not
particularly fall in love with the Allison approach to
imaging, which favored a broad soundstage and frontal blend
to pinpoint behavior. But even he admitted that the speaker
could play loud as hell.
Yes, with 2 mids and 2 tweeters, you obviously get substantial output.
Today, there are many 2 way systems, 1 woofer, one tweeter that can also
play loud as hell. As for Heyser not liking the "Allison approach to
imaging", I'd only say: what imaging?.

High Fidelity magazine reviewed the
smaller Model 9 version a few years later (only one tweeter
and midrange, instead of the two pairs of the Model One) and
they also were amazed at its maximum output abilities.

Hasn't High Fidelity been defunct for over 15 years? You don't think
anything has changed since then? Since you seem so adamant that these
Allison designs are "timeless", how about comparing to a modern speaker?


So, the so-called power limitations of the tweeter becomes
more of an academic issue than a practical issue, John.


So a tweeter that handles more power is what? Useless? Undesirable? Please
explain the downside. The downside of a low sensitivity tweeter is obvious,
especially when it becomes the limiting factor in the sensitivity of an
entire speaker system.

Howard Ferstler
No doubt.

In , dave weil wrote :

On Thu, 14 Apr 2005 10:25:57 +0200, Lionel
wrote:

In , dave weil wrote :

On Wed, 13 Apr 2005 22:33:26 -0400, Howard Ferstler
wrote:

This makes perfect sense given
the diameter of the voice coil, and the fact that high frequency
radiation in "soft diaphragm" tweeters is largely concentrated to the
area closest to the voice coil.

Sure. In any case, the tweeter has exemplary dispersion.
Perhaps the most notable thing about this is that the design
goes back three decades.

Is this supposed to be an indicator of quality?
If so, Quad has it beat by over a decade.

You should stop to write about Quad since you have proven that you don't
handle the subject correctly. ;-)

Then I guess you should have never written about accordions...didn't
stop YOU, did it?

Why Dave I have just shared some musical tastes with a guy ? All the rest
was coming from you.
You are a proven liar Dave... An artist of the accordion debating trade.

:-D

In , dave weil wrote :

On Thu, 14 Apr 2005 10:28:44 +0200, Lionel
wrote:

In , dave weil wrote :

I heard/felt what was possibly 8 hz at the Dead show that I saw a
couple of years back. It's just a guess though.

Do you measured the exact frequency ?

Look up the words "possibly" and "guess" and maybe you'll have the
answer to your question (even as you butchered it in the English
language).

I am just interested in trying to explain the value : "8 hz".
How can you know that it wasn't 12 or 11 or 7 hz.
I'm just smiling because this precision is a little bit ridicule and prove,
one more time, that you really don't know what you are speaking about.

You are more and more grotesque, Dave. I feel sorry for you.

On Thu, 14 Apr 2005 22:22:24 +0200, Lionel
wrote:

In , dave weil wrote :

On Thu, 14 Apr 2005 10:25:57 +0200, Lionel
wrote:

In , dave weil wrote :

On Wed, 13 Apr 2005 22:33:26 -0400, Howard Ferstler
wrote:

This makes perfect sense given
the diameter of the voice coil, and the fact that high frequency
radiation in "soft diaphragm" tweeters is largely concentrated to the
area closest to the voice coil.

Sure. In any case, the tweeter has exemplary dispersion.
Perhaps the most notable thing about this is that the design
goes back three decades.

Is this supposed to be an indicator of quality?
If so, Quad has it beat by over a decade.

You should stop to write about Quad since you have proven that you don't
handle the subject correctly. ;-)

Then I guess you should have never written about accordions...didn't
stop YOU, did it?

Why Dave I have just shared some musical tastes with a guy ? All the rest
was coming from you.

Ummm, I was talking with Howard when you butted in.

But that's cool. You just butt in whenever you like.

MINe 109 wrote:
In article ,
"Arny Krueger" wrote:

MINe 109 wrote:
In article ,
"Arny Krueger" wrote:

MINe 109 wrote:
In article ,
Howard Ferstler wrote:

That leaves the pipe organ. Now, I have a lot of pipe-organ
recordings and some do indeed, go down to below 25 or 30 Hz,
or even below 20 Hz. I have a couple that are strong to
16-18 Hz. However, while you may enjoy some organ concerts
here and there, my guess is that only rarely have those
organs hit the very bottom. They would not do that without
32-foot pipes in any case, and my guess is that the organ at
your establishment does not have those.

These days a lot of organs don't have 32 foot pipes, they have
electronics and subwoofers instead.

Even pipe organs sneak 'em in.

Exactly.

So, Stephen, I continue to believe that you have yet to hear
really deep bass from an audio system. Man, you do not know
what you are missing.

Given that Stephen is still flogging the dead vinyl horse, he's
got a lot of incentive to have a system with weak basss. Deep
bass
and vinyl are hard to mix. Furthermore, a lot of vinyl has the
deep bass removed or mono-ized in the interest of having a
recording that people could actually play. On the best day of
vinyl's life, deep bass meant short sides.

Dude, the cd player's hooked up to the same system.

So what?

So my choice of a speaker with relatively limited bass is unrelated
to
my including a turntable in my system.

Yeah, sure.

On Thu, 14 Apr 2005 22:29:11 +0200, Lionel
wrote:

In , dave weil wrote :

On Thu, 14 Apr 2005 10:28:44 +0200, Lionel
wrote:

In , dave weil wrote :

I heard/felt what was possibly 8 hz at the Dead show that I saw a
couple of years back. It's just a guess though.

Do you measured the exact frequency ?

Look up the words "possibly" and "guess" and maybe you'll have the
answer to your question (even as you butchered it in the English
language).

I am just interested in trying to explain the value : "8 hz".
How can you know that it wasn't 12 or 11 or 7 hz.

Mainly because I suspected that it was below the former (which I have
heard as a confirmed value) and above the latter, which I have never
heard. It might have been 9 hz, it might have been 10 hz. That's why I
estimated 8 hz.

I'm just smiling because this precision is a little bit ridicule and prove,
one more time, that you really don't know what you are speaking about.

It WASN'T precision, by definition, since I said "possibly" and
further qualified it by saying "It's just a guess though".

You sure are desperate to take me to task for anything but this is
really graspig at straws.

You are more and more grotesque, Dave. I feel sorry for you.

You've GOT to be kidding. This little exercise of yours is the
grotesque thing and truly pitiable. But feel free to keep banging your
head against the wall...

"dave weil" wrote in message
...
On Thu, 14 Apr 2005 10:25:57 +0200, Lionel
wrote:

In , dave weil wrote :

On Wed, 13 Apr 2005 22:33:26 -0400, Howard Ferstler
wrote:

This makes perfect sense given
the diameter of the voice coil, and the fact that high frequency
radiation in "soft diaphragm" tweeters is largely concentrated to the
area closest to the voice coil.

Sure. In any case, the tweeter has exemplary dispersion.
Perhaps the most notable thing about this is that the design
goes back three decades.

Is this supposed to be an indicator of quality?
If so, Quad has it beat by over a decade.

You should stop to write about Quad since you have proven that you don't
handle the subject correctly. ;-)

Then I guess you should have never written about accordions...didn't
stop YOU, did it?

OTH, anything with a bellows is appropriate for Lionel



----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----

In article ,
"Arny Krueger" wrote:

Me:
So my choice of a speaker with relatively limited bass is unrelated
to my including a turntable in my system.

Yeah, sure.

Weak.

In , dave weil wrote :

On Thu, 14 Apr 2005 22:22:24 +0200, Lionel
wrote:

In , dave weil wrote :

On Thu, 14 Apr 2005 10:25:57 +0200, Lionel
wrote:

In , dave weil wrote :

On Wed, 13 Apr 2005 22:33:26 -0400, Howard Ferstler
wrote:

This makes perfect sense given
the diameter of the voice coil, and the fact that high frequency
radiation in "soft diaphragm" tweeters is largely concentrated to
the area closest to the voice coil.

Sure. In any case, the tweeter has exemplary dispersion.
Perhaps the most notable thing about this is that the design
goes back three decades.

Is this supposed to be an indicator of quality?
If so, Quad has it beat by over a decade.

You should stop to write about Quad since you have proven that you don't
handle the subject correctly. ;-)

Then I guess you should have never written about accordions...didn't
stop YOU, did it?

Why Dave I have just shared some musical tastes with a guy ? All the rest
was coming from you.

Ummm, I was talking with Howard when you butted in.

Once again you are a *liar* Dave Weil.
You wasn't discussing with Howard you was attacking Arnold Krueger.

----------------------------------------------------------------------
Speakers are the weakest link
De:dave weil
Date:Mardi 12 Avril 2005 17:34:11
Forums:rec.audio.opinion

On Tue, 12 Apr 2005 05:51:43 -0400, "Arny Krueger"
wrote:

andy wrote:
I'm really critical of people who allege the superiority or even
adequacy of 30 to 50 year old speaker systems,

30-50 year old Quad 57? (a repaired one).

So, you're saying that Quad 57s are better than the 63s and later
models?

So much for Arnold's knowledge.

There's only one "later model".
--------------------------------------------------------------------------

But that's cool. You just butt in whenever you like.

You are a *pitiful* liar Dave Weil, deal with it

In , dave weil wrote :

On Thu, 14 Apr 2005 22:29:11 +0200, Lionel
wrote:

In , dave weil wrote :

On Thu, 14 Apr 2005 10:28:44 +0200, Lionel
wrote:

In , dave weil wrote :

I heard/felt what was possibly 8 hz at the Dead show that I saw a
couple of years back. It's just a guess though.

Do you measured the exact frequency ?

Look up the words "possibly" and "guess" and maybe you'll have the
answer to your question (even as you butchered it in the English
language).

I am just interested in trying to explain the value : "8 hz".
How can you know that it wasn't 12 or 11 or 7 hz.

Mainly because I suspected that it was below the former (which I have
heard as a confirmed value)

What have been confirmed the source signal oo the restitued one ?
Have you heard it or have you felt it ?
How many time have you heard this signal ?
How long before the Dead concert ?

and above the latter, which I have never
heard. It might have been 9 hz, it might have been 10 hz. That's why I
estimated 8 hz.

How can you know that it wasn't 11 hz ?

In , Clyde Slick wrote :


"dave weil" wrote in message
...
On Thu, 14 Apr 2005 10:25:57 +0200, Lionel
wrote:

In , dave weil wrote :

On Wed, 13 Apr 2005 22:33:26 -0400, Howard Ferstler
wrote:

This makes perfect sense given
the diameter of the voice coil, and the fact that high frequency
radiation in "soft diaphragm" tweeters is largely concentrated to the
area closest to the voice coil.

Sure. In any case, the tweeter has exemplary dispersion.
Perhaps the most notable thing about this is that the design
goes back three decades.

Is this supposed to be an indicator of quality?
If so, Quad has it beat by over a decade.

You should stop to write about Quad since you have proven that you don't
handle the subject correctly. ;-)

Then I guess you should have never written about accordions...didn't
stop YOU, did it?

OTH, anything with a bellows is appropriate for Lionel

This coming from the weakest regular of this NG. A coward who has publicly
abjured his faith...
Disgusting !!!!

MINe 109 wrote:
In article ,
"Arny Krueger" wrote:

Me:
So my choice of a speaker with relatively limited bass is
unrelated
to my including a turntable in my system.

Yeah, sure.

Weak.

Agreed Stephen, your comment was very weak.

In article ,
"Arny Krueger" wrote:

MINe 109 wrote:
In article ,
"Arny Krueger" wrote:

Me:
So my choice of a speaker with relatively limited bass is
unrelated
to my including a turntable in my system.

Yeah, sure.

Weak.

Agreed Stephen, your comment was very weak.

Thanks. I won a bet.

Stephen

MINe 109 wrote:
In article ,
"Arny Krueger" wrote:

MINe 109 wrote:
In article ,
"Arny Krueger" wrote:

Me:
So my choice of a speaker with relatively limited bass is
unrelated to my including a turntable in my system.

Yeah, sure.

Weak.

Agreed Stephen, your comment was very weak.

Thanks. I won a bet.

Next time Stephen bet with someone other than yourself, and you'll
show a positive cash flow.

MINe 109 said:

Thanks. I won a bet.

There's somebody willing to bet Krooger won't say something stupid? Lemme
at him!

"Lionel" wrote in message
...
In , Clyde Slick wrote :


"dave weil" wrote in message
...
On Thu, 14 Apr 2005 10:25:57 +0200, Lionel
wrote:

In , dave weil wrote :

On Wed, 13 Apr 2005 22:33:26 -0400, Howard Ferstler
wrote:

This makes perfect sense given
the diameter of the voice coil, and the fact that high frequency
radiation in "soft diaphragm" tweeters is largely concentrated to
the
area closest to the voice coil.

Sure. In any case, the tweeter has exemplary dispersion.
Perhaps the most notable thing about this is that the design
goes back three decades.

Is this supposed to be an indicator of quality?
If so, Quad has it beat by over a decade.

You should stop to write about Quad since you have proven that you don't
handle the subject correctly. ;-)

Then I guess you should have never written about accordions...didn't
stop YOU, did it?

OTH, anything with a bellows is appropriate for Lionel

This coming from the weakest regular of this NG. A coward who has publicly
abjured his faith...
Disgusting !!!!

Even though I don't attend synagogue, my yalmake is still not for sale.



----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----

"Arny Krueger" wrote in message
...
MINe 109 wrote:
In article ,
"Arny Krueger" wrote:

Me:
So my choice of a speaker with relatively limited bass is
unrelated
to my including a turntable in my system.

Yeah, sure.

Weak.

Agreed Stephen, your comment was very weak.



Well that certainly was 'robust'!!



----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----

On Fri, 15 Apr 2005 10:55:02 +0200, Lionel
wrote:

On Wed, 13 Apr 2005 22:33:26 -0400, Howard Ferstler
wrote:

This makes perfect sense given
the diameter of the voice coil, and the fact that high frequency
radiation in "soft diaphragm" tweeters is largely concentrated to
the area closest to the voice coil.

Sure. In any case, the tweeter has exemplary dispersion.
Perhaps the most notable thing about this is that the design
goes back three decades.

Is this supposed to be an indicator of quality?
If so, Quad has it beat by over a decade.

You should stop to write about Quad since you have proven that you don't
handle the subject correctly. ;-)

Then I guess you should have never written about accordions...didn't
stop YOU, did it?

Why Dave I have just shared some musical tastes with a guy ? All the rest
was coming from you.

Ummm, I was talking with Howard when you butted in.

Once again you are a *liar* Dave Weil.
You wasn't discussing with Howard you was attacking Arnold Krueger.

I replied to:

On Wed, 13 Apr 2005 22:33:26 -0400, Howard Ferstler
wrote:

This was completely separate from my off-hand comment (proven wrong,
BTW) to Arnold. This was in a technical discussion about Quad that
Howard was making.

This reply from me reply had NOTHING to do with Mr. Krueger.

You lose.

Again.

On Fri, 15 Apr 2005 11:04:02 +0200, Lionel
wrote:

In , dave weil wrote :

On Thu, 14 Apr 2005 22:29:11 +0200, Lionel
wrote:

In , dave weil wrote :

On Thu, 14 Apr 2005 10:28:44 +0200, Lionel
wrote:

In , dave weil wrote :

I heard/felt what was possibly 8 hz at the Dead show that I saw a
couple of years back. It's just a guess though.

Do you measured the exact frequency ?

Look up the words "possibly" and "guess" and maybe you'll have the
answer to your question (even as you butchered it in the English
language).

I am just interested in trying to explain the value : "8 hz".
How can you know that it wasn't 12 or 11 or 7 hz.

Mainly because I suspected that it was below the former (which I have
heard as a confirmed value)

What have been confirmed the source signal oo the restitued one ?

This is unintelligible.

Have you heard it or have you felt it ?

Both. At 12 hz, you do both. The dB level of the signal was fairly
loud, but it was nowhere near that of the Dead show, which was SURELY
at 115 dB+ (but don't worry, I'm not going to say anything more than
that).

How many time have you heard this signal ?

Once.

How long before the Dead concert ?

Quite a few years.

and above the latter, which I have never
heard. It might have been 9 hz, it might have been 10 hz. That's why I
estimated 8 hz.

How can you know that it wasn't 11 hz ?

I can't. That's why I qualified my remark TWICE. Heck, it could have
been 12 hz. Or 6 hz (although since my pants remained clean, I doubt
that it was that low).

If you can't take the statement for what it was, I suggest that you
calm down and have some French water. Or a nice Tokay.

dave weil wrote:

On Wed, 13 Apr 2005 22:52:28 -0400, Howard Ferstler
wrote:

You are correct. Most people do not really need a subwoofer
for music, especially classical music. I have A/B compared
my IC-20s running full range against the same speakers with
the Velodyne F1800 helping out and compared my Dunlavy
Cantatas running full range against the same speakers with
the Hsu TN1220 helping out, and the vast majority of the
time there is no difference that would matter to anybody.

Wouldn't it be "sensible" for you to argue against spending $2800 for
something that *might* be used once in a blue moon?

For some people, that last octave or half octave is pretty
important, particularly if they listen in a fairly large
room.

I spent $120 on an
overstock AR subwoofer that's good down to something like 28 hz.

Hsu and SVS both make under $1000 subs that can go flat to
20 Hz, and I have two of them on hand at my place right now.
Admittedly, the SVS is an early production model that I have
since modified to bring it up to current company standards.
I have reviewed both for The Sensible Sound, and also wrote
about the mods I did to the SVS.

I have compared some so-called "mid-priced" subs (several in
the $500 class, for instance, including a couple made by
companies who know what they are doing when it comes to
full-range speakers) that were supposedly decent down to 25
Hz or so to several of the lower-priced models made by Hsu
and SVS (meaning subs that cost from $300 to $500) and those
Hsu and SVS models mopped up the floor with them. This
involved both musical and test-tone inputs, with level
matching and quick switching. It was sometimes shocking to
see how much coloration those other subs generated compared
to the SVS and Hsu units, although it was clearly most
noticeable with those test-tone inputs.

I have formally reviewed those Hsu and SVS systems in The
Sensible Sound, by the way, and keep two of the Hsu units on
hand for the kind of comparison purposes mentioned above.

Just because a sub is "good down to something like 28 Hz"
does not qualify it as really all that good down to that
frequency. What you have may work just fine, but I do
suggest getting a good test disc (Delos has a good one in a
two-disc set, and Hi-Fi News and Record Review also produced
one a few years back) and doing some interesting work with
them.

Such a device can help with rock music, however, mainly
because it will prevent the punchy, moderately low bass from
pulverizing the woofers in typical full-range systems

Hardly. "Moderately low bass" is easily handled by most "full-range"
systems. Hell, my Allison CD-8s can easily handle all rock music
except for the most extreme volume levels.

You are right, but I probably misstated my case. At modest
levels you will have no problem. However, in a big room
(3000+ cubic feet or larger) pushing for rock-music levels
(at least with some program sources) is going to get those
otherwise fine woofers into trouble. Those systems have very
good and output-flat low-bass performance down to about 45
Hz, with clean but significantly attenuated response right
down to 30 Hz.

Below that frequency, all bets are off, but as you noted,
with rock music no bets need be taken, at least at
reasonable volume levels in typically sized rooms

Howard Ferstler

dave weil wrote:

On Wed, 13 Apr 2005 22:52:28 -0400, Howard Ferstler
wrote:

BTW, the temple that I attended in my youth HAD 32 ft pipes (IIRC) and
would occasionally utilize them. The whole sanctuary would rumble.

Wonderful feeling. In any case, now you have a good idea of
what a good subwoofer can do in a good room.

Oh, I've heard LOTS of low bass. That's part of the live music
experience.

Only if you attend organ concerts. Remember, bass down to
only 40 Hz is not LOW bass.

Howard Ferstler

Arny Krueger wrote:

MINe 109 wrote:
In article ,
Howard Ferstler wrote:

The orchestra (opera or otherwise) also does not go
particularly low. Any good "woofer" system that is flat to
40 Hz can handle just about anything an orchestra can throw
at it.

Much of the time this is probably true. Nevertheless, preserving deep
bass helps convey part of the sense of being there.

Yes. It can do this in two ways, at least with concert-hall
presentations.

First, a subwoofer can reproduce the low-frequency hall
"noise" that surrounds the listener at a live performance.
This will be subtle and probably would not be noticed at all
unless it was suddenly stopped. (Like hearing a clicking
clock stop that you had not previously noticed.) This
becomes particularly impressive with surround-sound
recordings or stereo recordings that have been given DSP
ambiance simulation work. The hall-space sound (which also
includes subtle higher-frequency clues, in addition to the
ultra-deep bass factor) then realistically envelopes the
listener. Unfortunately, a subwoofer may also be able to
reproduce the sound of that big truck that was idling its
engine outside of the hall during the recording session.

Second, it can get that occasional instrumental or
soundstage clue (thumping sounds or even combined harmonics
like what Stravinsky used at the beginning of The Firebird)
that a normal woofer would just not reproduce fully. The
effect will be subtle (more subtle than the hall noise
mentioned above), but it can be the icing on the kind of
cake that serious audio enthusiasts crave.

In that case, who cares?

Real audiophiles.

Yep. As I noted above.

That leaves the pipe organ. Now, I have a lot of pipe-organ
recordings and some do indeed, go down to below 25 or 30 Hz,
or even below 20 Hz. I have a couple that are strong to
16-18 Hz. However, while you may enjoy some organ concerts
here and there, my guess is that only rarely have those
organs hit the very bottom. They would not do that without
32-foot pipes in any case, and my guess is that the organ at
your establishment does not have those.

These days a lot of organs don't have 32 foot pipes, they have
electronics and subwoofers instead.

Yep. Ironically, Ed Villchur's Acoustic Research corporation
kind of pioneered using AR-1W woofers to augment organ
performance decades ago.

So, Stephen, I continue to believe that you have yet to hear
really deep bass from an audio system. Man, you do not know
what you are missing.

Given that Stephen is still flogging the dead vinyl horse, he's got a
lot of incentive to have a system with weak basss.

One would be hard pressed to obtain a vinyl recording that
had genuine deep bass. Supposedly, some were produced, but
they were specialty items. These days, many compact discs
have deep-bass signals that would shame even so-called
super-duper LP releases.

Deep bass and vinyl
are hard to mix. Furthermore, a lot of vinyl has the deep bass removed
or mono-ized in the interest of having a recording that people could
actually play. On the best day of vinyl's life, deep bass meant short
sides.

Yep. Yet, with a CD you can have deep bass on a release that
is over 70 minutes long. An LP that could approach that kind
of bandwidth (approach but probably not reach) would be
lucky to be 15 minutes on a side.

Howard Ferstler

MINe 109 wrote:

For a real sense of being there, Howard would embrace
stereo/multichannel subs.

I have tried it both ways, and found that a big mono sub,
crossed over low enough and mounted into a corner, will do
the job as well as stereo subs. (It may do even better,
because dual subs can generate inter-driver suckout
artifacts.) Yes, I know that guys like Dave Griesinger (whom
I admire greatly and even profiled in The Encyclopedia of
Recorded Sound) would disagree.

Incidentally, my main system does have dual subs. The F1800
handles the left, right, surround, and LFE channels and a
modified SVS unit (driven by a Hsu amp) handles the
center-channel bass. The two of them are in the left and
right front corners of my main room, about 20 feet apart.

Howard Ferstler

dave weil wrote:

On Wed, 13 Apr 2005 22:45:51 -0400, Howard Ferstler
wrote:

I heard/felt what was possibly 8 hz at the Dead show that I saw a
couple of years back.

One thing is for su you did not "hear" it, although you
may have heard harmonic overtones. I am curious about what
kind of instrument they used to generate an 8 Hz signal.

I'm sure that it was synthesized.

Maybe a super dbx 120x.

I have a standard unit. It would take some work to do the
mod. The AudioControl Phase Coupled Activator subharmonic
bass generator has a switchable option that allows the user
to generate subharmonics that get down REALLY low. (I
reviewed one of these devices in issue 68 of The Sensible
Sound.) I have found that feature to be musically pointless,
however. Other than that, with some pop-music sources the
two devices (with the PCA run in its standard mode) can be a
lot of fun.

Unfortunately, being analog devices, with any direct-digital
input neither can be used, meaning that with DVD movies
employing the digital hookup they are useless. However, with
conventional laserdisc inputs (analog outputs and not DD or
DTS outputs) they can soup up older action/adventure movies.

Howard Ferstler

In article ,
Howard Ferstler wrote:

MINe 109 wrote:

For a real sense of being there, Howard would embrace
stereo/multichannel subs.

I have tried it both ways, and found that a big mono sub,
crossed over low enough and mounted into a corner, will do
the job as well as stereo subs. (It may do even better,
because dual subs can generate inter-driver suckout
artifacts.) Yes, I know that guys like Dave Griesinger (whom
I admire greatly and even profiled in The Encyclopedia of
Recorded Sound) would disagree.

So would that jj guy who used to hang out here.

Incidentally, my main system does have dual subs. The F1800
handles the left, right, surround, and LFE channels and a
modified SVS unit (driven by a Hsu amp) handles the
center-channel bass. The two of them are in the left and
right front corners of my main room, about 20 feet apart.

I'm sure that's fine for home theater .1, but you're missing out for
well-recorded two and three channel.

Stephen

In article ,
Howard Ferstler wrote:

Arnie:
Deep bass and vinyl
are hard to mix. Furthermore, a lot of vinyl has the deep bass removed
or mono-ized in the interest of having a recording that people could
actually play. On the best day of vinyl's life, deep bass meant short
sides.

Yep. Yet, with a CD you can have deep bass on a release that
is over 70 minutes long. An LP that could approach that kind
of bandwidth (approach but probably not reach) would be
lucky to be 15 minutes on a side.

Fortunately, I have a cd player.

Stephen

dave weil wrote:

On Wed, 13 Apr 2005 22:33:26 -0400, Howard Ferstler
wrote:

This makes perfect sense given
the diameter of the voice coil, and the fact that high frequency radiation
in "soft diaphragm" tweeters is largely concentrated to the area closest to
the voice coil.

Sure. In any case, the tweeter has exemplary dispersion.
Perhaps the most notable thing about this is that the design
goes back three decades.

Is this supposed to be an indicator of quality?
If so, Quad has it beat by over a decade.

Not when it comes to wide-angular dispersion.

Howard Ferstler

On Fri, 15 Apr 2005 14:12:16 -0400, Howard Ferstler
wrote:

dave weil wrote:

On Wed, 13 Apr 2005 22:52:28 -0400, Howard Ferstler
wrote:

You are correct. Most people do not really need a subwoofer
for music, especially classical music. I have A/B compared
my IC-20s running full range against the same speakers with
the Velodyne F1800 helping out and compared my Dunlavy
Cantatas running full range against the same speakers with
the Hsu TN1220 helping out, and the vast majority of the
time there is no difference that would matter to anybody.

Wouldn't it be "sensible" for you to argue against spending $2800 for
something that *might* be used once in a blue moon?

For some people, that last octave or half octave is pretty
important, particularly if they listen in a fairly large
room.

Well, for some, spending $9000 on a new set of Quads to squeeze out
the best of midrange is pretty important. For others, spending $2000
on a used set of Quads for the same purpose might be the ticket. For
someone else, spending almost $4 grand on a tube amp that has several
modes of operation that gives different audio presentations might be
important as well. I wouldn't demand that anyone else take those paths
though.

I spent $120 on an
overstock AR subwoofer that's good down to something like 28 hz.

Hsu and SVS both make under $1000 subs that can go flat to
20 Hz, and I have two of them on hand at my place right now.

But I didn't want (or need) to spend more than a couple of hundred
dollars for a subwoofer. That could certainly change in the future
though.

I'm just surprised that with all of the mods you've done to your
listening room, that you didn't bother to install a Nousaine/Devil
approved attic subwoofer. You stopped short of state-of-the-art,
didn't ya?

On Fri, 15 Apr 2005 14:13:14 -0400, Howard Ferstler
wrote:

dave weil wrote:

On Wed, 13 Apr 2005 22:52:28 -0400, Howard Ferstler
wrote:

BTW, the temple that I attended in my youth HAD 32 ft pipes (IIRC) and
would occasionally utilize them. The whole sanctuary would rumble.

Wonderful feeling. In any case, now you have a good idea of
what a good subwoofer can do in a good room.

Oh, I've heard LOTS of low bass. That's part of the live music
experience.

Only if you attend organ concerts. Remember, bass down to
only 40 Hz is not LOW bass.

Well, I have attended organ concerts (something that I don't think
you've admitted to doing), but I've also heard plenty of sub 40 hz
stuff at live rock shows as well.

On Fri, 15 Apr 2005 14:30:17 -0400, Howard Ferstler
wrote:

Incidentally, my main system does have dual subs. The F1800
handles the left, right, surround, and LFE channels and a
modified SVS unit (driven by a Hsu amp) handles the
center-channel bass. The two of them are in the left and
right front corners of my main room, about 20 feet apart.

Of course, you can't always tell when both are operational.

On Fri, 15 Apr 2005 14:35:53 -0400, Howard Ferstler
wrote:

dave weil wrote:

On Wed, 13 Apr 2005 22:45:51 -0400, Howard Ferstler
wrote:

I heard/felt what was possibly 8 hz at the Dead show that I saw a
couple of years back.

One thing is for su you did not "hear" it, although you
may have heard harmonic overtones. I am curious about what
kind of instrument they used to generate an 8 Hz signal.

I'm sure that it was synthesized.

Maybe a super dbx 120x.

I have a standard unit

That was a joke, Howard.

I have the "standard" unit as well, but it's been loaned out for a
couple of years.

John Atkinson wrote:

Howard Ferstler wrote:

But still not particularly wide, compared to what good
dynamic speakers with smallish midrange (2 to 4 inch) and
tweeter (3/4 to one inch) drivers can do.

Did you look at these dispersion graphs, Mr. Ferstler? Yes,
the flat panel of the Innersound speaker has the very
restricted treble radiation pattern to which you were
referring but the MartinLogan doesn't, thus proving your
first statement above incorrect in all aspects.

OK, the ML system disperses wider. However, it is still no
great shakes.

Hey, I actually decided to read the reviews (I rarely read
your magazine these days, John) and I have to admit that you
do a pretty good job. I even had a really good electrical
engineer who is a very serious audio buff and audio writer
tell me that you were one of the best speaker testers
around, and I have stated elsewhere (including in some
recording reviews) that you are an excellent recording
engineer. However, both he and I remain mystified that you
continue to associate yourself with a magazine that often
spouts poppycock. Well, perhaps you just need a job.

compare the radiation patterns of the two electrostatic
speakers I referenced above. Whether it is due to the ML's
curved diaphragm or to some other factor, their panel does
indeed offer quite good lateral dispersion.

Out to how many degrees off axis?

How hard is it for you to click on a link, Mr. Ferstler?
If you actually looked at the dispersion graphs that I
published you would find the answer to your question.

I found the 3-D graph rather hard to interpret.

Needless to say, my Allison IC-20 systems satisfy most
wide-dispersion requirements.

Except that these speakers do not have wide dispersion, Mr.
Ferstler, nor have you provided any measurements that support
this claim.

Do not have wide dispersion? Give me a break. Do not posture
about this, John. You know as well as I that whatever one
may think of the Allison designs, poor dispersion is not one
of their characteristics.

I am not "posturing," whatever you mean by that word, Mr.
Ferstler. You have written at length about the supposed
wide dispersion of the Allison tweeter, but it appears to be
no better than any other 3/4" unit in this respect.

Even John Stone stated that the driver approximates what a
1/2-inch job could do. I have comparison graphs between good
3/4-inch units and the Allison tweeter, and above 8 kHz the
latter is easily superior at extreme angles. Above 10 kHz it
is no contest.

And those extreme angles are important. As I have noted in a
couple of magazine articles and also in one of my books,
while the angular coverage from 0 to 45 degrees off is the
same as from 45 degrees out to 90 degrees, the "area"
covered by the latter angle response is almost 2.5 times as
large as the area covered by the former. That partially
explains why choppy response at wide angles can have a
negative impact on speaker sound in typical (not
acoustically treated) listening rooms.

I note
also that you have also _not_ measured its dispersion.

Well, I have Roy Allison's own measurements. Perhaps you
think that he either fudged the results or did not do the
work correctly.

In
addition, 1) it is naive for you to assume that the drive-unit's
dispersion is not modified by the speaker baffle and 2) no
matter how wide the tweeter's dispersion, this will be
radically altered by the use of _two_ of them. Two laterally
spaced tweeters offer a narrower horizontal radiation pattern
than one alone.

I have polar response curves run by Allison that show you to
be in error. But, yes, there are interference effects that
will impact the smoothness of the first-arrival signals.
This is no big deal to me, but it might be to guys like you
and perhaps others who consider tight imaging to be the
end-all criteria for good speaker sound.

The original reviews of the IC-20 systems by both High
Fidelity Magazine and Stereo Review commented upon their
ultra-wide dispersion.

But what measurements did those magazines publish to
support that contention? And how where those measurements
performed? Perhaps I am mistaken, but I can't remember
the late Julian Hirsch performing either polar plots or
the waterfall dispersion plots that I perform in Stereo
Review.

You write for Stereo Review? I thought that magazine had
merged with Video to become Sound & Vision. Hey, just
kidding. I know what you mean. But in any case, it is
preposterous to assume that a system like the IC-20 has poor
dispersion, and I again think that you are basically
grandstanding to win some points for your team.

And again if I remember correctly, High Fidelity only
performed sound _power_ measurements.

They measured on-axis performance, front-hemisphere
performance, and sound-power performance. Dave Moran has
measured the tweeter, as well as the full system (and also a
number of other Allison systems) over a wide angle and found
it to have exemplary dispersion. Of course, all one has to
do is listen to the system when comparing it to a
narrower-dispersion job (or even the more forward-facing,
single-panel Allison jobs) to realize just how spacious the
systems sound.

Even if the systems had only one forward-facing panel they
would have those Allison drivers dispersing widely clear out
to 90 degrees off axis.

But without measured support for this statement, you have
no basis to make it, unless you label it as being your _opinion_.

Well, I have the measurements of those other individuals,
and of course one need only look at the system and look at
the driver-response curves Allison made available to realize
that, ipso facto, the system will have superb dispersion.

However, they have dual panels, each angled out 45 degrees
from dead ahead, meaning that they have extremely wide
dispersion to each side and out to 135 degrees off axis.

No, this results in _narrower_ dispersion on the primary
frontal axis, with complex lobing apparent.

At some frequencies, but not all of them. Also, the
angled-panel mounting result in different effects from what
you will get with drivers located side-by-side on one panel.
If what you say is true, a system with drivers mounted all
the way around its horizontal circumference would be the
worst dispersing system possible.

Howard Ferstler

dave weil wrote:

On Wed, 13 Apr 2005 23:04:56 -0400, Howard Ferstler
wrote:

Yep, it works (at least for you and other fans of the
speaker), but that does not mean that it works better than a
number of other superb designs that are more conventional.

But you don't know that.

Right. But even you have not compared the speaker directly
to other notable designs. You have listened to it open
ended, and have no idea how well some competing models might
do in comparison.

But he's actually HEARD it.

How does your statement apply to what YOU'VE written about the
speaker?

I have only mentioned what another rather influential and
knowledgeable individual wrote about it (well, said about it
during a lecture). For all I know, the damned thing hung the
moon. But in principle the system has characteristics that
should make some purists a bit apprehensive.

Howard Ferstler

On Fri, 15 Apr 2005 14:35:53 -0400, Howard Ferstler
wrote:

dave weil wrote:

On Wed, 13 Apr 2005 22:45:51 -0400, Howard Ferstler
wrote:

I heard/felt what was possibly 8 hz at the Dead show that I saw a
couple of years back.

One thing is for su you did not "hear" it, although you
may have heard harmonic overtones. I am curious about what
kind of instrument they used to generate an 8 Hz signal.

I'm sure that it was synthesized.

Maybe a super dbx 120x.

I have a standard unit. It would take some work to do the
mod. The AudioControl Phase Coupled Activator subharmonic
bass generator has a switchable option that allows the user
to generate subharmonics that get down REALLY low. (I
reviewed one of these devices in issue 68 of The Sensible
Sound.) I have found that feature to be musically pointless,
however. Other than that, with some pop-music sources the
two devices (with the PCA run in its standard mode) can be a
lot of fun.

BTW, when I said "synthesized" and mentioned the 120X, it was a play
on words. I'm sure that the signal was generated BY A SYNTHESIZER,
probably triggered by a sensor on a drum pad. You see, Mickey Hart is
a percussionist and this was during his improvisational "drumz/space"
segment, which lasted about 20 minutes.

I DO have a recording of that very show and it would be interesting to
see how much of the signal was captured on the CD. I remember that
that shirts flapped and chests tightened. You could feel it in your
bones. Thankfully, it only lasted for a few seconds at most. It was
close to being painful to the body.

BTW, per the new Lionel Convention, I'm not claiming that it was
*exactly* 8 hz, as I wasn't wired with a frequency analyzer at the
time, but I'm quite sure that it was the lowest "tone" I've ever heard
and it was a very high dB level.

Here's Mickey's take on the system:

http://www.mickeyhart.net/site2003_dev/0617.html

Note that they use sound-cancelling technology for the stage
performers.

And here's the system itself:

http://www.meyersound.com/news/2003/dead/index.htm

That's EIGHTEEN subwoofers, Howard.

THAT'S a high-end "hi-fi", Howard.

MINe 109 wrote:

In article ,
Howard Ferstler wrote:

MINe 109 wrote:

Yes, what are they doing instead?

They are being electrically delayed by circuitry within the
speaker. A real purist would wonder if this was causing some
kind of distortion as the delays become longer at the
outermost rings.

A real realist would study up to see what the mechanism was.

Well, one thing for su it involves an analog delay line,
and something like that should make a serious audio purist
(one who fantasizes about LP recordings, tube amps, green
ink, super wires, etc., etc.) a bit nervous.

Kessler's presence makes any commentary suspect.

But he's a published author.

Books, or just articles in tweako magazines?

If a delay line is involved, the signal is no longer
pristine. But, hey, it may still be clean enough to satisfy
guys like you and me. It may offend the sensibilities of the
purists, however, although many of them may love the speaker
without having a clue about how much signal manipulating is
going on inside.

Then no "delay line" is involved.

There is no way to electrically delay the signals going to
the concentric rings without a delay line. The delay
requirement basically mandates the use of a delay line in
the analog domain.

Of course, it
seems that you're ignorant of the dispersion qualities of your own
favored speakers, so perhaps we can discount your opinion on the matter.

Huh? I have polar curves run from the middle bass on up to
16 kHz. Admittedly, Allison ran them, and I suppose that if
you think he was a con artist then those polar plots might
just be bogus. I don't however.

JA had a different view of your tweeter.

http://user.tninet.se/~vhw129w/mt_audio_design/

JA has an ax to grind and turf to protect. That he would
contest the findings and designs of Roy Allison exhibits
more hubris than I can calculate.

Howard Ferstler

dave weil wrote:

On Wed, 13 Apr 2005 23:04:56 -0400, Howard Ferstler
wrote:

However, you're
speaking from ignorance, and willful ignorance at that.

Well, while I have not heard the speakers, I have read about
them and I know what inherent disadvantages large panel
drivers will exhibit. In addition to the Lip****z paper I
have mentioned, I have the simple common-sense issue of
having a large radiating area sending signals to a small
receptor (the ear). The signals from that large area surface
cannot all reach the ear simultaneously. As a result, you
get substantial comb-filtering artifacts.

Hardly.

Not in the case of the Quads.

Nonsense. Just take a tape measure and compare the different
distances from the extreme edges of the moving diaphragm to
the ear with the distance from the center to the ear.
Obviously, there are going to be cancellation artifacts
(comb filtering) within the direct-field signals because of
this.

If you examime the dimensions of the
speaker, you might realize why you are wrong in this case, especailly
when you compare the dimensions with the dimensions of *your*
speaker's array.

I never said that the IC-20 was able to put forth a
completely coherent, non-comb-filtered direct-field signal,
although when set to its "focus" mode, with the
inward-angled array dominating, it certainly can. However,
what it can put out is flat power, and can disperse widely
over the full 180-degree frontal axis. This flat power
literally buries any anomalies we have with the direct-field
signal, because the reverberant field so dominates.

On the other hand, with the Quad 57 we most definitely have
the direct-field signal dominating, and this means that any
comb-filtering artifacts it exhibits will not be buried in
the reverberant field. The effects will be clearly audible.

Note that the IC-20 is indeed a line source system, but not
one with a fixed length driver array. The tweeter line is
short enough to not cause serious vertical beaming problems
over the line's operating range. The longer midrange line
(overlaying the tweeter line) does not cause serious
vertical beaming problems over that line's operating range.
It is a controlled-length line source.

Howard Ferstler

MINe 109 wrote:

In article ,
Howard Ferstler wrote:

MINe 109 wrote:

For a real sense of being there, Howard would embrace
stereo/multichannel subs.

I have tried it both ways, and found that a big mono sub,
crossed over low enough and mounted into a corner, will do
the job as well as stereo subs. (It may do even better,
because dual subs can generate inter-driver suckout
artifacts.) Yes, I know that guys like Dave Griesinger (whom
I admire greatly and even profiled in The Encyclopedia of
Recorded Sound) would disagree.

So would that jj guy who used to hang out here.

Yeah. Incidentally, I profiled JJ, too in the Encyclopedia,
even though I disagree with him about the impact of
crossover frequencies between the 40 and 90 Hz range. I
simply cannot see the big deal. The location of the
satellites have a much more profound impact on the perceived
sense of bass spaciousness than the use of dual subs or
ultra-low crossover points.

Incidentally, my main system does have dual subs. The F1800
handles the left, right, surround, and LFE channels and a
modified SVS unit (driven by a Hsu amp) handles the
center-channel bass. The two of them are in the left and
right front corners of my main room, about 20 feet apart.

I'm sure that's fine for home theater .1, but you're missing out for
well-recorded two and three channel.

I do a lot more music listening than I do movie watching. It
is easy to fast-check the impact of dual vs single bass
locales with my main system. All I have to do is switch back
and forth with the remote control between the bass below 90
Hz being reproduced by the single F1800 sub or being
reproduced by the two, double-woofer arrays of my spaced
apart (12 feet) IC-20 systems. (Quick pushes on the button
allows for slick A/B work.) As long as I am not listening to
music with strong bass below 35 Hz, the relative bass levels
will be the same. And the sense of space will be the same,
too.

Incidentally, as best I can tell Griesinger (and perhaps JJ,
too) played around with subwoofers flanking the listener and
not out in front. The idea was to have the bass frequencies
coming at the listener from cross-correlated locations.
While this might result in some interesting effects
(Griesinger had his design working with the double-sub
feature of the Lexicon processors that he helped design), I
am not sure that it enhanced realism any more than dipolar
speakers (or Bose 901 speakers, for that matter) bouncing
sound off of the front wall enhance realism. They just make
for more interesting, and possibly more pleasant, sound
reproduction.

Howard Ferstler