LaScala Sonic Detail Improvement for only $220.98

[ClaudeJ1]

Just finished reading all of the posts, I have heard of this upgrade.

 

The question that I have is this:

 

Do the spiders, cones and surrounds on the original Klipsch LaScala 1980s wear out, has their performance degraded over 35 years?

Not really, no, unless abused,  because they are well protected from the environment. Sealed back, and a buried slot. Besides when a horn gets over 100 db, the cone moves only about 1 MM. Unlike a subwoofer cone, which gets 20X the excursion, this is not a problem for an original woofer.

Edited September 26, 2015 by ClaudeJ1

[Bubo]

 

Just finished reading all of the posts, I have heard of this upgrade.

 

The question that I have is this:

 

Do the spiders, cones and surrounds on the original Klipsch LaScala 1980s wear out, has their performance degraded over 35 years?

Not really, no, unless abused,  because they are well protected from the environment. Sealed back, and a buried slot. Besides when a horn gets over 100 db, the cone moves only about 1 MM. Unlike a subwoofer cone, which gets 20X the excursion, this is not a problem for an original woofer.

 

 

Thanks for the quick reply. I would have thought that they fatigue, but do have to admit every time I walk in the room my reaction is "that sounds good".

 

A bit off topic, but the caps have to be at the end of the road. Crites sells Sonicaps (if I recall correctly) any favorites or suggestions.

 

I just recapped one pair of my Heresy 1s and they sing, also recapped the Yamaha amp with them, so perhaps both are now happy.

 

I'm thinking recap the crossovers, then go from there the CT 125s have fans, the mid horn drivers sound so sweet with female vocal they may be the last thing I would change.

 

Recap, CT-125s?, then replace the woofers.

 

On the current stock woofer the EQ setting that I like is definitely hotter on the 400 Hz than the rest of the bars.

Edited September 26, 2015 by Bubo

[ClaudeJ1]

 

 

Just finished reading all of the posts, I have heard of this upgrade.

 

The question that I have is this:

 

Do the spiders, cones and surrounds on the original Klipsch LaScala 1980s wear out, has their performance degraded over 35 years?

Not really, no, unless abused,  because they are well protected from the environment. Sealed back, and a buried slot. Besides when a horn gets over 100 db, the cone moves only about 1 MM. Unlike a subwoofer cone, which gets 20X the excursion, this is not a problem for an original woofer.

 

 

Thanks for the quick reply. I would have thought that they fatigue, but do have to admit every time I walk in the room my reaction is "that sounds good".

 

A bit off topic, but the caps have to be at the end of the road. Crites sells Sonicaps (if I recall correctly) any favorites or suggestions.

 

I just recapped one pair of my Heresy 1s and they sing, also recapped the Yamaha amp with them, so perhaps both are now happy.

 

I'm thinking recap the crossovers, then go from there the CT 125s have fans, the mid horn drivers sound so sweet with female vocal they may be the last thing I would change.

 

Recap, CT-125s?, then replace the woofers.

 

On the current stock woofer the EQ setting that I like is definitely hotter on the 400 Hz than the rest of the bars.

 

Dean G recommends dropping the mids by 3 db and using a 6.8 uF cap on the Xover for that reason. Changing the woofer will thin the lower bass a bit on the LaScala but will give you glorious midrange from the bass bin. you should be using a sub anyhow below 100 Hz. with a LaScala, or build my Quarter Pie bass horn.

[Coytee]

I agree about the drivers.  I got mine in 1979 and they're still sounding fine.

[ClaudeJ1]

I have LaScala's from the 80's I cannot tell any degradation from my woofers, if anything they sound stronger dropping 3 db from the crossover as previous post suggested. I have used Dayton caps from Parts Express. One of the better lower priced caps for crossovers. I did change my tweeters because I changed to a first order crossover with no autotransformer and the stock tweeter will not take a first order without failing. 

I did the same thing and used Crites tweeters. Much smoother than K-77

[Bubo]

If I want to make improvements or changes in incremental steps, this is what I understand:

 

Based on the above posts, and a conversation (2-3 years ago) with B Crites and the Klipsch factory support guy, the drivers in the LaScala don't wear out under normal circumstances. The capacitors, on the other hand do have an end of life, the transformer and inductor rarely fail (it would probably require an amp incinerating failure to fry the inductor or transformer).

 

First:

 

Update the 3 caps on the AA crossover, from the schematic in the pinned section.

 

Stock: Sonicaps from Crites or others inc Parts Express brand.

To me, stock always sounded very good

 

2x  2uF capacitors

1x 13uF

 

Alternative Crossover update to lower the volume mids by 3db aka 50% decrease in power to Squawker.

This is done to flatten the output across the bass and mids?

I currently use an EQ to add output at the 400Hz point and rolling off into the up and down freqs from this point.

 

2x 2uF caps

1x 6.8 uF cap

 

Both of these updates-mods are stand-alone and can be listened to and evaluated without further mods or repairs.

 

 

Second

 

This step could be either replace the K-77 (matched ?) phenolic tweeters with the Crites CT-125 EV driver with custom Crites Lens and titanium diaphragm. OR Replace the woofer with the Crites stamped Woofer $$, or Eminence Kappa 15C $, also mentioned above is the K-44 Factory $$$ woofer.

 

http://www.parts-express.com/eminence-kappa-15c-15-driver-4-ohm--290-459

 

Both the tweeter and the woofer "upgrades" are standalone changes and require no mods to the crossover or anything else.

 

Third

 

If the K-77 is replaced with the Crites CT 125, as an option after moving to the CT-125.....the crossover point between the Squawker and the CT-125 can be lowered to take advantage of the increased range of the CT-125.

 

Thread on CT-125  topic, one of many?

https://community.klipsch.com/index.php?/topic/153576-ct-125-tweeters-in-la-scala/

 

Thread on Crossovers

https://community.klipsch.com/index.php?/topic/148350-la-scala-crossover-upgrade-options/

 

Volti take on LaScala

http://www.klipschupgrades.com/lascalaupgrades2.shtml

 

More horns + ALK

http://www.alkeng.com/trachorn.html

 

Alethia's take on custom crossovers

http://www.aletheiaaudio.com/Services.html

 

 

 

Crossover Options with CT-125: Do nothing leave at 400 and 6,000Hz, replace crossover 400 and 4,500 Hz, somehow modify existing crossover to 400 and 4,500. Forgot to mention the ALK Universal, I'm sure there are others....

 

The existing crossover may be modified, I don't know how.

 

OR

 

The AA crossover can be replaced with a new A 4500 from Crites

 

http://www.critesspeakers.com/bk-sound-type-a4500-crossov.html

 

"Problem with this is that the K-55 mid-range driver is pressed really hard to reach 6000hz.  It would be much more linear in it's operation if the highest frequencies it has to reproduce were in the 4500hz area."

 

Note: I'm guessing that PK the Designer was aware of this, and perhaps no better option was available than the EV K-77 tweeter, AND OR  the mid-range K-55 is so sweet with the voice that it is better to leave as much of the voice as possible on the K-55 up to 400- 6KHz. Maybe if we had the engineer's notes we could know how the decision was made, I'm sure lots of trial and "does this sound better than"........

 

 

My opinion the LaScala:

 

PK was a very good audio engineer, everything was done for a reason. Speakers that sound good, sell better.

 

Was the mid range 400-6,000 intentionally boosted to put the human (Female) voice more forward aka Hear the Angels Singing? The K-55 really makes the angels sing.

 

The low end could be better, a design trade off

Edited September 26, 2015 by Bubo

[ClaudeJ1]

The man who takes advice from too many builders builds a crooked house.

[Bubo]

The man who takes advice from too many builders builds a crooked house.

 

Claude,

 

I'm just trying to get it all on one post, for myself and anyone that comes after me.

 

As you can tell from my post, I am probably going to replace the caps on the AA crossover and keep it stock. If I'm happy, I may stop there since the consensus is that the stock drivers don't degrade over time. I have so may other projects  that have to be done. There is also $$

 

Again, thanks for starting and maintaining this thread.

Edited September 27, 2015 by Bubo

[muel]

If I want to make improvements or changes in incremental steps, this is what I understand:

 

Based on the above posts, and a conversation (2-3 years ago) with B Crites and the Klipsch factory support guy, the drivers in the LaScala don't wear out under normal circumstances. The capacitors, on the other hand do have an end of life, the transformer and inductor rarely fail (it would probably require an amp incinerating failure to fry the inductor or transformer).

 

First:

 

Update the 3 caps on the AA crossover, from the schematic in the pinned section.

 

Stock: Sonicaps from Crites or others inc Parts Express brand.

To me, stock always sounded very good

 

2x  2uF capacitors

1x 16uF

 

Alternative Crossover update to lower the volume mids by 3db aka 50% decrease in power to Squawker.

This is done to flatten the output across the bass and mids?

I currently use an EQ to add output at the 400Hz point and rolling off into the up and down freqs from this point.

 

2x 2uF caps

1x 6.8 uF cap

 

Both of these updates-mods are stand-alone and can be listened to and evaluated without further mods or repairs.

 

 

Second

 

This step could be either replace the K-77 (matched ?) phenolic tweeters with the Crites CT-125 EV driver with custom Crites Lens and titanium diaphragm. OR Replace the woofer with the Crites stamped Woofer $$, or Eminence Kappa 15C $, also mentioned above is the K-44 Factory $$$ woofer.

 

http://www.parts-express.com/eminence-kappa-15c-15-driver-4-ohm--290-459

 

Both the tweeter and the woofer "upgrades" are standalone changes and require no mods to the crossover or anything else.

 

Third

 

If the K-77 is replaced with the Crites CT 125, as an option after moving to the CT-125.....the crossover point between the Squawker and the CT-125 can be lowered to take advantage of the increased range of the CT-125.

 

Crossover Options with CT-125: Do nothing leave at 400 and 6,000Hz, replace crossover 400 and 4,500 Hz, somehow modify existing crossover to 400 and 4,500.

 

The existing crossover may be modified, I don't know how.

 

OR

 

The AA crossover can be replaced with a new A 4500 from Crites

 

http://www.critesspeakers.com/bk-sound-type-a4500-crossov.html

 

"Problem with this is that the K-55 mid-range driver is pressed really hard to reach 6000hz.  It would be much more linear in it's operation if the highest frequencies it has to reproduce were in the 4500hz area."

 

Note: I'm guessing that PK the Designer was aware of this, and perhaps no better option was available than the EV K-77 tweeter, AND OR  the mid-range K-55 is so sweet with the voice that it is better to leave as much of the voice as possible on the K-55 up to 400- 6KHz. Maybe if we had the engineer's notes we could know how the decision was made, I'm sure lots of trial and "does this sound better than"........

 

 

My opinion the LaScala:

 

PK was a very good audio engineer, everything was done for a reason. Speakers that sound good, sell better.

 

Was the mid range 400-6,000 intentionally boosted to put the human (Female) voice more forward aka Hear the Angels Singing? The K-55 really makes the angels sing.

 

The low end could /e better, a design trade off

AA network takes a 13uF cap not 16.   I'm told you can substitute a 12uF without issue if you can't find the 13. 

Tweeters would be near the bottom of my list of things to worry about but I like the K-77.  You might want to go with your alternative crossover update if you use Sonicaps or Daytons.  Those caps are cheap enough it wouldn't cost much to experiment.  

[Bubo]

 

If I want to make improvements or changes in incremental steps, this is what I understand:

 

Based on the above posts, and a conversation (2-3 years ago) with B Crites and the Klipsch factory support guy, the drivers in the LaScala don't wear out under normal circumstances. The capacitors, on the other hand do have an end of life, the transformer and inductor rarely fail (it would probably require an amp incinerating failure to fry the inductor or transformer).

 

First:

 

Update the 3 caps on the AA crossover, from the schematic in the pinned section.

 

Stock: Sonicaps from Crites or others inc Parts Express brand.

To me, stock always sounded very good

 

2x  2uF capacitors

1x 16uF

 

Alternative Crossover update to lower the volume mids by 3db aka 50% decrease in power to Squawker.

This is done to flatten the output across the bass and mids?

I currently use an EQ to add output at the 400Hz point and rolling off into the up and down freqs from this point.

 

2x 2uF caps

1x 6.8 uF cap

 

Both of these updates-mods are stand-alone and can be listened to and evaluated without further mods or repairs.

 

 

Second

 

This step could be either replace the K-77 (matched ?) phenolic tweeters with the Crites CT-125 EV driver with custom Crites Lens and titanium diaphragm. OR Replace the woofer with the Crites stamped Woofer $$, or Eminence Kappa 15C $, also mentioned above is the K-44 Factory $$$ woofer.

 

http://www.parts-express.com/eminence-kappa-15c-15-driver-4-ohm--290-459

 

Both the tweeter and the woofer "upgrades" are standalone changes and require no mods to the crossover or anything else.

 

Third

 

If the K-77 is replaced with the Crites CT 125, as an option after moving to the CT-125.....the crossover point between the Squawker and the CT-125 can be lowered to take advantage of the increased range of the CT-125.

 

Crossover Options with CT-125: Do nothing leave at 400 and 6,000Hz, replace crossover 400 and 4,500 Hz, somehow modify existing crossover to 400 and 4,500.

 

The existing crossover may be modified, I don't know how.

 

OR

 

The AA crossover can be replaced with a new A 4500 from Crites

 

http://www.critesspeakers.com/bk-sound-type-a4500-crossov.html

 

"Problem with this is that the K-55 mid-range driver is pressed really hard to reach 6000hz.  It would be much more linear in it's operation if the highest frequencies it has to reproduce were in the 4500hz area."

 

Note: I'm guessing that PK the Designer was aware of this, and perhaps no better option was available than the EV K-77 tweeter, AND OR  the mid-range K-55 is so sweet with the voice that it is better to leave as much of the voice as possible on the K-55 up to 400- 6KHz. Maybe if we had the engineer's notes we could know how the decision was made, I'm sure lots of trial and "does this sound better than"........

 

 

My opinion the LaScala:

 

PK was a very good audio engineer, everything was done for a reason. Speakers that sound good, sell better.

 

Was the mid range 400-6,000 intentionally boosted to put the human (Female) voice more forward aka Hear the Angels Singing? The K-55 really makes the angels sing.

 

The low end could /e better, a design trade off

AA network takes a 13uF cap not 16.   I'm told you can substitute a 12uF without issue if you can't find the 13. 

Tweeters would be near the bottom of my list of things to worry about but I like the K-77.  You might want to go with your alternative crossover update if you use Sonicaps or Daytons.  Those caps are cheap enough it wouldn't cost much to experiment.  

 

Good catch, I just checked the drawing again. Corrected above

[ClaudeJ1]

 

The man who takes advice from too many builders builds a crooked house.

 

Claude,

 

I'm just trying to get it all on one post, for myself and anyone that comes after me.

 

As you can tell from my post, I am probably going to replace the caps on the AA crossover and keep it stock. If I'm happy, I may stop there since the consensus is that the stock drivers don't degrade over time. I have so may other projects  that have do be done. There is also $$

 

Again, thanks for starting and maintaining this thread.

 

No problem. Replacing the caps for me opened up the detail in the K400 horn but replacing the woofer opened up the detail in the upper midbass/midrange. Most of all.

[Welborne]

I am glad I read this. A La Scal user here. I rotated the LS by 90 degree so it sits on one of its otherwise resonating panel, then put crossover, mid horn (a Le Cleac'h flare) and tweeter on top that damps the other side panel by their weight. This kills much of the annoying infamous resonance but still some are left there and I suspect its the doghouse. Will putting in 15c cure this?

[Coytee]

If you ever go active it seems it can be PEQ'ed out or at least, down a significant amount.  (-7 db's, 148Hz, Q=8)

[RRR]

I am glad I read this. A La Scal user here. I rotated the LS by 90 degree so it sits on one of its otherwise resonating panel, then put crossover, mid horn (a Le Cleac'h flare) and tweeter on top that damps the other side panel by their weight. This kills much of the annoying infamous resonance but still some are left there and I suspect its the doghouse. Will putting in 15c cure this?

 

No, brace them.

[Islander]

I am glad I read this. A La Scal user here. I rotated the LS by 90 degree so it sits on one of its otherwise resonating panel, then put crossover, mid horn (a Le Cleac'h flare) and tweeter on top that damps the other side panel by their weight. This kills much of the annoying infamous resonance but still some are left there and I suspect its the doghouse. Will putting in 15c cure this?

 

With some music, the La Scala side panels may seem to resonate, but it is not audible.  The speakers have a peak at 148 Hz, but that is a consequence of the shape of the horn, and has nothing to do with "resonating" side panels.

 

The proof of this is that the La Scala II has the very same peak at 148 Hz, although its much stiffer 1" thick sidewalls do not move at all.

 

Most people don't find the actual sound objectionable, but stiffening the side panels seems like an easy fix and a cool thing to do, although it doesn't address the issue of the sound peak at all.

 

If the peak really is an issue, the best, and maybe most expensive, way to fix it is to convert the speakers to JubScala spec, which adds an active electronic crossover that can EQ out the peak.

[RRR]

 

I am glad I read this. A La Scal user here. I rotated the LS by 90 degree so it sits on one of its otherwise resonating panel, then put crossover, mid horn (a Le Cleac'h flare) and tweeter on top that damps the other side panel by their weight. This kills much of the annoying infamous resonance but still some are left there and I suspect its the doghouse. Will putting in 15c cure this?

 

With some music, the La Scala side panels may seem to resonate, but it is not audible.  The speakers have a peak at 148 Hz, but that is a consequence of the shape of the horn, and has nothing to do with "resonating" side panels.

 

The proof of this is that the La Scala II has the very same peak at 148 Hz, although its much stiffer 1" thick sidewalls do not move at all.

 

Most people don't find the actual sound objectionable, but stiffening the side panels seems like an easy fix and a cool thing to do, although it doesn't address the issue of the sound peak at all.

 

If the peak really is an issue, the best, and maybe most expensive, way to fix it is to convert the speakers to JubScala spec, which adds an active electronic crossover that can EQ out the peak.

 

 

I could hear mine when the volume was up with no problem, never braced them though.

[Welborne]

If its a peak, has anyone designed a passive notch filter circuit to flatten it in the crossover?

[Quiet_Hollow]

The proof of this is that the La Scala II has the very same peak at 148 Hz....

Where did you get that from? Got a link? 

 

Real data for the La Scala II is awfully scarce. 

[Bubo]

This has probably been discussed many times, but I'll ask the question.

 

There is clearly a performance curve in the LaScala woofer section that is more efficient at the hump that Claude plotted for us.

 

The question then becomes, is the hump the result of the K-33 design, or the the Horn design, or both?

 

IMHO trying to fix it after it occurs, is always a bad engineering solution and probably the reason some crossovers are not well received, like patching the outside of a tire.

 

If the Hump is noticeable, and undesirable, I would think it would be better to attenuate it in an EQ before it reaches the Amplifier and Crossover.

 

Without Klipsch's Engineer notes, if they exist, it's hard to know what his intentions were. The hump may have helped to sell speakers, or even been a compensation for the tube amplifiers of the day or the way sound travels in auditoriums, churches and theaters aka he did it for a reason.

 

Like so many good things, Moray surfaced this article on a different thread.

 

I doubt if Klipsch gave everything away in an industry paper, but enough to make it interesting, and help sales.

 

I assume the Industry Theater Speaker he is comparing to is the Altec A-7 2-Way, drivers unknown at this minute.

 

Does a 2 in driver in a 2-way speaker extend the highs in a flatter response than the A-7 high end did? Or the Altec 802- pick your letter D G etc.....

 

There is also the question of which Altec Horn Klipsch was comparing to, 811, 511 or something else, but ringing is a common complaint with these two.

 

Then there is the question of which horn sounds the most lifelike with female voice, the K-55V is so sweet it sets a high mark for comparison.

LaScala AES Pre-print.pdf

Edited November 10, 2015 by Bubo

[Bubo]

I thought some tube response curves might help illuminate the hump issue. Not.

 

The magazine test is interesting, the manufacturers response is scorching or worse.

 

http://www.stereophile.com/content/dynaco-stereo-70-ii-power-amplifier-measurements

 

http://www.stereophile.com/content/dynaco-stereo-70-ii-power-amplifier-manufacturers-comment