New tweeter results for 1986 La Scala (SMAHLv2/DE-120 versus K-77M)

[Dave MacKay]

 A few days ago I replaced the original tweeters (K-77M drivers and standard lenses) in my 1986 La Scalas with SMAHL v2 lenses and DE-120 drivers from @Dave A The improvement made by the new tweeters is nothing short of astounding! 

 

My La Scalas are as original except:

• I reinforced the cabinets by laminating 3/8" baltic birch to the sides, top, and bottom to reduce resonance (and to address some cosmetic damage)
• I replaced the original AL networks with new AA networks from Crites

 

To be frank, having wanted La Scalas for more than 40 years before finally getting a pair (in July), I was a bit underwhelmed by them. Sure, the music was clean and free of distortion, and they could play louder than I could stand, but some music (e.g., Springsteen, U2, Prince) just didn't sound as good as I'd hoped.

 

Changing the tweeters has fixed that. I am absolutely delighted!

 

I used REW to take some measurements before and after changing the tweeters. Because I was focused on the tweeters, I measured a range from 4500Hz to 20kHz. The room conditions, equipment, and all parameters were kept the same. I took three measurements before and after changing the tweeters. I "burned in" the new tweeters for about 8 hours before measuring them. This chart shows the average of the measurements, with 1/12 smoothing:

 

Here are my old tweeters:

 

And here are the new SMAHLv2/DE-120 tweeters:

 

I had planned to paint the SMAHL v2 lenses black, but they look so good I may just leave them as they are.

 

Others might not be keen on such a change, but I couldn't be happier. YMMV, but I wanted to share my experience on the forum.

 

I'm grateful to members of the forum ( especially @ClaudeJ1) for making me aware of the SMAHL and to @Dave A for an excellent product.

[Marvel]

13 minutes ago, Dave MacKay said:

Springsteen, U2, Prince) just didn't sound as good as I'd hoped.

I have a couple Springsteen albums... they haven't sounded good on anything. Maybe I don't play them loud enough for the bass and treble to come up.

 

[garyrc]

PLEASE IGNORE AND MOVE FOUR POSTS AHEAD FOR ANOTHER  TRY!

 

[garyrc]

P.S.  I listen mainly to classical music, jazz, folk, film music, etc; full orchestra sounds great on most CDs, SACDs, DVD-As, Blu-rays, etc., but when a friend brought over Springsteen, it sounded pretty terrible.  Later I tried again, and it sounded bad on any speaker in the house, including, at the time, Khorns, Belle, Heresy II, ADC, JBL, etc.  Maybe I just don't know what Springsteen is supposed to sound like.

[Marvel]

I don't know, Gary. Was his bsnd known to be really loud? If playback is expected to be the same, it might explain some of it.

[Dave MacKay]

3 hours ago, garyrc said:

Here is what the K77s in my Klipschorn AK4s above 4.5K (Xovers) look like

after room treatment.  The main divisions are 5 dB.  As you can see, the sweep crosses the 0 line at 12.27K, and the top of the curve is about - 4db at 17K Hz.  If I want it (on certain recordings), adding 3 dB with a treble control, provides a slightly higher bulge below 12.27K and brings ~~ 15K to almost flat.

 

For the below, I wish I had the original documentation -- maybe someone else does.

Here are three K77/T35s.  Look only above 4.5KHz, to match use in the Klipschorn AK4 or AK5 and the lower cut-off of the @Dave MacKaygraph.  The RED plot is from a Klipschorn "of unknown history," IIRC, the others from separate, detached K77/T35s, all without EQ.

 

I wasn't able to open either image. If others are having the same problem, would you please re-post them?

[garyrc]

5 hours ago, Dave MacKay said:

 

I wasn't able to open either image. If others are having the same problem, would you please re-post them?

 

Even I can't open them now.  I'll work on it.

Here, try this:

 

Here is what the K77s in my Klipschorn AK4s above 4.5K (Xovers) look like after room treatment and Audyssey Flat.  The main divisions are 5 dB.  As you can see, the sweep crosses the 0 line at 12.27K, and the top of the curve is about - 4db at 17K Hz.  If I want it (on certain recordings), adding 3 dB with a treble control, provides a slightly higher bulge below 12.27K and brings ~~ 15K to almost flat.

 

For the below, I wish I had the original documentation -- maybe someone else does.

Here are three K77/T35s.  Look only above 4.5KHz, to match use in the Klipschorn AK4 or AK5 and the lower cut-off of the @Dave MacKaygraph.  The RED plot is from a Klipschorn "of unknown history," IIRC, the others from separate, detached K77/T35s, all without EQ.

 

[CWOReilly]

16 hours ago, Marvel said:

I have a couple Springsteen albums... they haven't sounded good on anything. Maybe I don't play them loud enough for the bass and treble to come up.

 

There's a lot of distortion in lots of Springsteen recordings. Louder makes it worse. Sad but true.

[pcbiz]

On 1/2/2022 at 9:05 PM, garyrc said:

P.S.  I listen mainly to classical music, jazz, folk, film music, etc; full orchestra sounds great on most CDs, SACDs, DVD-As, Blu-rays, etc., but when a friend brought over Springsteen, it sounded pretty terrible.  Later I tried again, and it sounded bad on any speaker in the house, including, at the time, Khorns, Belle, Heresy II, ADC, JBL, etc.  Maybe I just don't know what Springsteen is supposed to sound like.

 

I have a friend who was at the first Audio Engineering Society (AES) meeting to exhibit CDs. Everyone was impressed with the improved audio quality, until it came to Springsteen. The complaints included "This is horrible! It sounds like it was recorded in the basement with cheap microphones." The fact is, that's exactly how it was recorded.

[HPower]

On 1/2/2022 at 2:48 PM, Dave MacKay said:

 A few days ago I replaced the original tweeters (K-77M drivers and standard lenses) in my 1986 La Scalas with SMAHL v2 lenses and DE-120 drivers from @Dave A The improvement made by the new tweeters is nothing short of astounding! 

 

My La Scalas are as original except:

• I reinforced the cabinets by laminating 3/8" baltic birch to the sides, top, and bottom to reduce resonance (and to address some cosmetic damage)
• I replaced the original AL networks with new AA networks from Crites

 

To be frank, having wanted La Scalas for more than 40 years before finally getting a pair (in July), I was a bit underwhelmed by them. Sure, the music was clean and free of distortion, and they could play louder than I could stand, but some music (e.g., Springsteen, U2, Prince) just didn't sound as good as I'd hoped.

 

Changing the tweeters has fixed that. I am absolutely delighted!

 

I used REW to take some measurements before and after changing the tweeters. Because I was focused on the tweeters, I measured a range from 4500Hz to 20kHz. The room conditions, equipment, and all parameters were kept the same. I took three measurements before and after changing the tweeters. I "burned in" the new tweeters for about 8 hours before measuring them. This chart shows the average of the measurements, with 1/12 smoothing:

 

Here are my old tweeters:

 

And here are the new SMAHLv2/DE-120 tweeters:

 

I had planned to paint the SMAHL v2 lenses black, but they look so good I may just leave them as they are.

 

Others might not be keen on such a change, but I couldn't be happier. YMMV, but I wanted to share my experience on the forum.

 

I'm grateful to members of the forum ( especially @ClaudeJ1) for making me aware of the SMAHL and to @Dave A for an excellent product.

 

Hey Dave,

 

Do you have any pics of the front of your LSs showing Dave's lens in place?

 

I have been thinking about ordering a pair for my rebuilt 1982 LSs.

 

 

[Budman]

-

 

 

 

[Drewg]

Here are my ‘86 LaScalas with Dave A’s tweeters.




Sent from my iPhone using Tapatalk

[CWOReilly]

79 CW and 75 LS

[HPower]

Thanks for those pics guys!

 

With the way I rounded my cabinets, and more specifically the horn openings, I am not sure how nice the SMAHLv2 lenses will look in my opening?

 

 

Maybe if I was to pull the lens back a bit with something like a 1/2in spacer, it would keep to the look I have now?

Or  @ClaudeJ1 @Dave A  might that compromise some of the sonic benefits of Dave's lens, not being flush with the front of the motherboard?

 

 

 

 

[Dave A]

One of the key things that make these work well is the mouth of the horn is flush with the front of the motorboard. Only you can decide if esthetics of looks trumps esthetics of sound. Personally if I was worried I would paint them black and go from there. 

 

  Nice looking set of speakers by the way as I happen to like the Pro look.

[ClaudeJ1]

2 hours ago, HPower said:

I have been thinking about ordering a pair for my rebuilt 1982 LSs.

Just take advice from NIKE ads. Just do it! I promise you won't regret it.

[ClaudeJ1]

On 1/3/2022 at 6:29 AM, garyrc said:

 

Even I can't open them now.  I'll work on it.

Here, try this:

 

Here is what the K77s in my Klipschorn AK4s above 4.5K (Xovers) look like after room treatment and Audyssey Flat.  The main divisions are 5 dB.  As you can see, the sweep crosses the 0 line at 12.27K, and the top of the curve is about - 4db at 17K Hz.  If I want it (on certain recordings), adding 3 dB with a treble control, provides a slightly higher bulge below 12.27K and brings ~~ 15K to almost flat.

 

For the below, I wish I had the original documentation -- maybe someone else does.

Here are three K77/T35s.  Look only above 4.5KHz, to match use in the Klipschorn AK4 or AK5 and the lower cut-off of the @Dave MacKaygraph.  The RED plot is from a Klipschorn "of unknown history," IIRC, the others from separate, detached K77/T35s, all without EQ.

 

The DE-120 uses superior, modern matertials for tweeters and leaves the relatively "sluggish" Phenolic (great for midrange) Diaphragms "in the dust," so to speak. If you look at my curves, you can see a rising response at 20 Khz. which, effectively compensates for that "old man" hearing so many of us have. LOL.

 

Electrically EQing the crap out of a sluggish diaphragm is NOT the same as having one that is Acoustically, and Naturally "EQ'd." There's a certain Delicacy to the sound that still ends up missing.

 

Like PWK was once quoted as saying: "If a driver can reach 19 Khz. it will also do 10 Khz. much better" or something like that, I'd have to ask Jim Hunter.

[HPower]

29 minutes ago, Dave A said:

One of the key things that make these work well is the mouth of the horn is flush with the front of the motorboard. Only you can decide if esthetics of looks trumps esthetics of sound. Personally if I was worried I would paint them black and go from there. 

 

  Nice looking set of speakers by the way as I happen to like the Pro look.

 

I kind of figured that flush mount would be the optimal position.

Is there any sonic preference between the wood version vs. the aluminium version?

If not, I think the wooden version would be easier to paint black.

 

I like the pro look as well, although mine did not start out as Industrials...

 

 

 

 

[HPower]

22 minutes ago, ClaudeJ1 said:

Just take advice from NIKE ads. Just do it! I promise you won't regret it.

 

I don't think you have ever steered me wrong Claude!

 

But I am sure that's what all us junkies think about their pushers. 😉

 

[Dave A]

17 minutes ago, HPower said:

Is there any sonic preference between the wood version vs. the aluminium version?

If not, I think the wooden version would be easier to paint black.

No difference. Personally if I wanted black I would paint the aluminum ones. Yeah I guess you could paint the wood too but buying wood is, to me anyway, a choice made for esthetics.