AES Pre-print re LaScala by PWK

[WMcD]

I had posted this pre-print as a set of .gif files some years ago. People were having problems printing it.

rjrbass is asking questions about the LS in another thread but I think this deserves its own thread.

The AES sent the hard copy to me with two pages to a sheet. That is why it is sideways.

Unrelated to that issue: It is interesting that the drawings show the doghouse rotated 90 degrees from the production model.

Gil

gilpubs

LaScala AES Pre-print.pdf

[DrWho]

Interesting - PWK has the bass bin as 4-6dB down from 60-100Hz...not 50Hz. He also mentions that it's got a sensitivity of 107dB [] Is this an early prototype with different drivers or something?

[pauln]

Thanks, Gil

This article touches on a lot of great points:

The 107dB is interesting, I guess from the coner gain which makes a good reference for home placement vs anechoic testing

Mention of path lengths (Time alignment) assessment

And mention that the basis of design was to support live music and reproduce the live instrument fundamentals (of that time)

Nice graphs, too; no wonder the LS is loud, live, lusty, and long lived.

[freddyi]

FWIW here's a guestimate simulation - if it bears resemblence (?), then PWK carefully adjusted K33E motor strength and damping (how much volume in LS/Belle dog houses?)

2-K33 specs vs B&C 15TRX woofer 2.83v

http://img150.imageshack.us/img150/3718/lsc2cnw4.jpg

2-K33 specs vs K43 spec 2v

http://img63.imageshack.us/img63/6357/lsc2vde4.jpg

[WMcD]

My guess is that the 107 dB rating has been correct all along.

You look at the LB patent and the mid (a Belle mid K-500 and K55?) is not knocked down with an autotransformer. The K-77 is increased 3 dB with an autotransformer.

So it could be that the K-Horn is lossy because of the 3 x 13 restriction and general losses in the bass horn twists. Not so with a cleaner design like the LS. We might still have that restriction, though.

It is food for thought that here we have a not well publicized 1965 article. While the LS has long had a lot of fans, it has long been dismissed as a PA or DJ speaker, unworthy of audiophiles. Then, with some tweeking (perhaps by Roy D.?) it gets to a Stereophile Class A rating, almost 50 years later.

Gil

[pauln]

"The La Scala is perhaps one of the most perplexing, unexplainable mysteries in the audiophile world. When I looked at its specs on paper, I almost didn't want to listen. Who is willing to waste time on a frequency response of 53Hz to 17,000Hz +/-4 dB these days? But when the music came through those horns, I was flabbergasted for the second time. These big boxes could image. Not only that, they made sound in such a warm, airy, expansive and relaxed manner that the listener became totally absorbed in the music. With the La Scala, you don't think in HiFi terms. My earlier concern about frequency response had melted away by the refined sound and the spontaneously natural timbre...

" ...The La Scalas have their own way of conjuring up the magic of music. They are so un-hifi that you won't bother to look for the pin-point imaging or high resolution layering - and yet nothing is missing from the total sonic tableau. You are listening with your heart rather than with your ears."

From the 6 moons Feb 2007 review of the Trends TA10 Tripath amp

http://www.6moons.com/audioreviews/trends/ta10_3.html

The Trends TA10 just won a 2007 "Digital" Amp Shootout (the TA10 is not digital, it's pulse width modulated analog)

http://www.stereomojo.com/SHOOTOUT2007INTEGRATEDS.htm

[BS Button]

Makes you wonder what would've come out about resonance in the bass bin had they left it horizontal?

BS

[Marvel]

IIRC, there have been some pics posted of those earlier models with the doghouse rotated to the horizontal position. One of the awful things about that desing was that the access hatch is quite visible on the side of the cabinet. Not a very polished look, and would receive a low WAF.

Bruce

[ClaudeJ1]

I prefer the sound of a K-43 in a LaScala rather than a K-33.....not so much for the power handling, but more for the higher BL product, and higher output at 400 Hz. to mate with the K55/K400. It thins the bass out a bit at the bottom, but one should use a sub with a LaScala anyhow. Interesting to see the Industrial version had a K-43.

the K33, does a good job at trying to extend the bass, but if you want that, a Khorn is a better choice overall.I think that a LaScalaq with a K-43 and a good subwoofer (an MWM or a a Tapped Horn to really get low) sounds better than a Khorn (lived with the Khorn LaScala Khorn 3-channel for 30 years).