In article ,
Howard Ferstler wrote:

MINe 109 wrote:

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

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.

Poor deluded ML.

However, as best I can tell, those diaphragms are solidly
attached at the edges and therefore have to flex as they
move back and forth. This would almost certainly result in
resonances at some frequencies. This is why that whenever a
system like that is measured for power response the curve
will exhibit a large degree of choppiness. Combine this with
the comb-filtering artifacts you will get with any
large-diaphragm driver when it is dealing with short
wavelength frequencies, and it is easy to see why
large-panel systems cannot exhibit smooth frequency
response.

Ah, the myth of electrostatic resonance.

Dipole highs, monopole lows, something's got to give.

This actually has not got much to do with anything. At low
frequencies, all systems tend to radiate in a bipolar or
full circular manner and not as a dipole. Well, you could
get a dipolar response down low with a dipolar woofer
(Carver did this a while back), but the response will roll
off fast below a certain point. Carver compensated with some
huge levels of equalization.

ML's been working on the problem for years without solving it.

I guess you've never heard of Gradient.

Then again, ML isn't Quad.

Nor Magnepan.

Magnepan would be in the same position of the others,
although by using optimized drivers of varying size they
overcome some resonance artifacts. However, the line-source
generated comb-filtering artifacts would remain. Generally,
those are simply perceived as a rolloff above 5 to 8 kHz and
not as anything erratic.

Generally, the earlier Quad models were very directional,
and so the listener had to toe them in and remain pretty
much locked into the sweet spot. (This kind of rigid
listening is not my cup of tea at all.) That directionality
basically resulted in the direct field being dominant at
midrange and treble frequencies, making the speakers perform
like huge headphones.

Agreed. A "problem" with all bipolar speakers.

Especially if you live in an aircraft hangar.

This comment makes no sense whatsoever.

No dipole added depth.

Those who like that kind of somewhat sterile behavior would
obviously prefer such speakers.

I'm one of them.

It's hard to think of a dipole promiscuously splashing sound around as
being sterile.

It is highly directional. Yes, there are delayed front-wall
reflections, but the hugely reduced ceiling/floor and
side-wall reflections tends to make them far less spacious
sounding than wider-dispersion systems. However, the
front-wall reflections, if the systems are pulled out far
enough, will lend a sense of frontal depth to the sound.
However, remember that this is not recorded depth. It is
just a room-generated artifact that usually sounds pleasant.

Pleasant, yes. Wouldn't want any artificially added depth, though. At
least you're admitting they aren't giant headphones.

If Howard knew how to use URLs, he could look at this and follow the
links:

http://user.tninet.se/~vhw129w/mt_au...n/quadpage.htm

Note that while HiFi New rated the ESL-57 as "the greatest
hi-fi product of all time," that rather tweaky magazine is
an English journal and would happily award the prize to one
of their own.

It's just chauvinism? You're crying sour grapes.

As for Ken Kessler, well I think that most of what he says
about anything is bunk. Basically, this article is a typical
tweako "white paper" that does not say much of interest at
all.

You stopped reading at the second paragraph! Too bad, you'd have
recognized a companion spirit. Or is it uninteresting because the
descriptions based on use and listening are different from your
preconceptions?

Plenty of schematics, etc, in the links.

One qualification, however. I will say that the point-source
concept is a good one, but I am not sure that Quad has
pulled it off all that well. There is a lot of electrical
manipulation involved, and arcane stuff like that ought to
have you tweakos wringing your worrisome little hands.

Since you haven't heard them, you have no idea if Quad has achieved
their goals or not.

Please explain how Quad does that "electrical manipulation".

And Quad are anti-tweako, input capacitors aside.

Stephen