Quote Originally Posted by theaudiohobby
RGA,

Next time do your research before you post, you have scored an own goal, follow this thread and read the context of the post, John used Lynn's article to attack Kevlar. For the record, John Ashman posted that article in October 2004, a full three months before this thread started, and quoted from the article on a least one occasion before thread in question, FTR in that article, Lynn said
in other words, as previously stated, it is the implementation that matters, not the actual material.

I decided not to resist posting this article by Lynn Olsen for you to mull over everytime you dream of the Ongaku, Lynn said of the LNPA 150 Class AB transistor amplifier

and that was almost ten years ago, I leave you work out the implications of his comments.
you should also know that Lynn's ONLY kevlar exception is that of scanspeak not of B&W -- did you e-mail to ask which one Lynn doesn;t like -- it's B&W just so you know which of course should be obvious since at the time B&W was the ONLY major company making speakers with Kevlar...so i'm not sure you were under the impression he was obviously referring to B&W or not -- but now you know.


Are you under some delusion that I believe AN is perfect or the best? That if I post a great response to an item that someone won't ever like something a bit better...The ongaku has been improved and downright changed 3 times since 1994 -- and there is the UK version which is about half the price now.

"The Ongaku, by far, had the worst THD and power measurements ... 22W at 3%
distortion. It also made the Ariel sound better than any electrostat I've
ever heard ... in fact, the best sound I'd heard in many years. It
certainly sounded better than anything I heard at the 1994 Winter CES. So
what's going on here? Maybe THD is simply measuring the wrong thing"

Suffice it to say it's a great amplifier which he liked more than the Reichert. The SS amp was also sent packing -- there is no indication he likes it any better than theRecihert or the ongaku the latter isn't at a sane price which is why he had to return it -- he can't afford it...not many can. So if you read what he says clearly he likes the SS amp as his favorite at a SANE price -- which means it is NOT his favorite at ANY price. Though I would be interested to hear this SS amp because very few are at all good so I'm sure he's probably right that this one is a standout.

I'm sure he can find better than the 1993-94 Ongaku --- he just needs to look up the new ones.

"From Lynn
"At the present, though, even the best Kevlar, carbon-fiber, or aluminum
designs show at least one high-Q peak at the top of the working range,
requiring a sharp crossover, a notch filter, or preferably both to control
the peak. Unfortunately, this peak usually falls in a region between 3 and
5 kHz, right where the ear is most sensitive to resonant coloration."

B&W Corssover 4khz (as many have said a BAD choice)

"There are highly-reviewed (by the large-circulation "underground"
magazines[ie B&W]) 2-way speakers that use 7" Kevlar drivers[ie B&W] crossed over to
metal-dome tweeters[ie B&W]. Technically, these loudspeakers operate with uniform
motion over the range of both drivers; in practice, though, the crossovers
are hard pressed to remove all of the energy from the Kevlar breakup region
between 3 and 5 kHz."

"The reviews of these particular 2-way speakers go on at considerable, and
amusing, length about the trials in finding an amplifier that "revealed"
the full quality of the loudspeaker. In reality, the reviewer was forced to
use an amplifier that was particularly free of coloration in the region
where the Kevlar driver was breaking up. Since most audiophiles and
reviewers are unfamilar with the direct sound (and measurements) of
commonly-used raw drivers, they can't evaluate how much "Kevlar sound", or
"aluminum sound", remains as a residue in the finished design."

"This is a problem, by the way, that plagues all [ALL means B&W] current 2-way Kevlar,
metal, or carbon-fiber loudspeakers ... at the current state of the art,
the 6.5" or 7" drivers are forced to operate right up to the edge of their
working ranges in order to meet the tweeter in a moderate-distortion
frequency range."

"If you lower the crossover frequency, tweeter IM distortion skyrockets,
resulting in raspy, distorted high frequencies at mid-to-high listening
levels; if you raise the crossover frequency, the Kevlar breakup creeps in,
resulting in a forward, aggressive sound at moderate listening levels[B&W 4khz}, and
complete breakup at high levels (unlike paper cones, Kevlar, metal, and
carbon fibers do not go into gradual breakup)."

Which is why they don;t sound very cohesive

"I should add, by the way, that I like Kevlar and carbon-fiber drivers very
much ... but they are difficult drivers to work with, with strong resonant
signatures that must be controlled acoustically and electrically."

"As mentioned above, rigid cones have advantages, but are difficult to damp
completely. A different approach is to use a cone material that is made
from a highly lossy material (traditionally, this was plastic-doped paper,
but this has been supplanted by polypropylene in most modern loudspeakers).
The cone then damps itself, progressively losing energy as the impulse from
the voice coil spreads outwards across the cone surface. The choice of
spider and surround are then much less critical.

This type of material[POLYPROLYENE] typically measures quite flat and also allows a
simple 6dB/Octave crossover; personally, though, I don't care for the sound
of most polypropylene drivers, finding them rather vague and
blurry-sounding at low-to-medium listening levels. {Read Paradigm et al} Without access to a B&K
swept IM distortion analyzer, I have to resort to guesswork, but I strongly
suspect that this type of cone has fairly high IM distortion since it is
quite soft. In addition, it is quite difficult to make a material that has
perfectly linear mechanical attenuation; in practice, distortion creeps in
when you actually want a progressive attenuation of energy over the surface
of the cone."

And back to Kevlar -

"A unique and quite desirable property of the latest Scan-Speak Kevlar
drivers is a smooth rolloff region above the usual Kevlar peak. All of the
other Kevlar drivers [ALL MEANS B&W] (that I have measured and listened to) have chaotic
breakup regions; the Scan-Speaks are the only ones [ONLY MEANS NOT B&W that appear
well-controlled in this region..."

B&W does not use Scan-Speak (Note the part ALL OF THE OTHERS).

Now do you believe that Lynn Olsen has NEVER in his life designing and reviewing has NEVER EVER HEARD A SINGLE B&W SPEAKER USING KEVLAR??????????????

PLEASE!!