Heresy I Slow Motion Mods

[pcbiz]

9 hours ago, Racer X said:

Not to dissuade you from your vintage LaScala dream, but as someone who moved from LaScala to Cornwall to Heresy, the LaScala is the most deficient in bass.  No low bass to speak of and a huge bump in bass horn response around 100 to 200 hz.

That's what mods are for.

[Racer X]

I really do not believe any mod will tame the nature of the LaScala bass horn.  On the plus side it will play very loud and clear, but not low and uncolored.

[Chris A]

1 hour ago, Racer X said:

I really do not believe any mod will tame the nature of the LaScala bass horn.  On the plus side it will play very loud and clear, but not low...

This is basically correct.

 

1 hour ago, Racer X said:

but not...uncolored.

 

This is actually incorrect--in fact very incorrect.  Note the measured harmonic and modulation distortion output...at 110 dB (1 metre)!

 

 

One of the great advantages of the La Scala is the performance of its 180 degree folded horn bass bin.  There are no direct radiating bass bins that can do all of the above.  I'm amazed that more loudspeakers don't take advantage of this design (now ~60 years old).  Only the knock-off Volti Vittoria and perhaps one other (expensive)  handmade European loudspeaker reuses the La Scala's design--to great advantage.

 

Chris

[pcbiz]

1 hour ago, Racer X said:

I really do not believe any mod will tame the nature of the LaScala bass horn.  On the plus side it will play very loud and clear, but not low and uncolored.

 

I'm sure the bass will be satisfactory for me. Maybe not for you, but fine for me. Try these "mods" and let me know how it goes.

 

Mod 1: Place unobtrusive braces in the bass bin.

Mod 2: Place the speakers on two foot solid wood tables, and isolate the bottom of the bass bin and of the table's feet as best you can.

Mod 3: Get a subwoofer

Mod 4: Get an ALK crossover with the one octave lower feature.

Mod 5: Listen to the modded La Scalas for as long as you'd like, then buy brand new AL5s.

[geoff.]

@pcbiz, have you tried the ALK Universals in your Chorus 2s?

[pcbiz]

22 minutes ago, geoff. said:

@pcbiz, have you tried the ALK Universals in your Chorus 2s?

No... I've thought about pulling them out of my Heresy pair to experiment, but I'll leave it alone as Al isn't supporting it. It would probably sound great and then flub out at high volumes. 

[Racer X]

Chris A, I certainly defer to your astute analysis.  By uncolored I simply meant frequency response, flatness.  This is of course room dependent.  I believe others have noted the large rise in response in the LaScala bass horn.  This can be countered, corrected with equalization.  I still remember when I plotted the response in my too small room I could not believe the large resonance.

[Islander]

6 hours ago, Racer X said:

Chris A, I certainly defer to your astute analysis.  By uncolored I simply meant frequency response, flatness.  This is of course room dependent.  I believe others have noted the large rise in response in the LaScala bass horn.  This can be countered, corrected with equalization.  I still remember when I plotted the response in my too small room I could not believe the large resonance.

 

The rise in bass response in the La Scala bass horn is not due to any resonance.  It’s a feature/glitch of the dimensions of the horn.  The La Scala II bass horn has dimensions that are almost identical to those of the original La Scala, and it has the same size peak at 148 Hz.  This is in spite of being built of 1” MDF, which is much stiffer than the 3/4” plywood of the original Scala, and much less prone to any resonances.

 

How high is the peak?  The EQ setting to flatten the peak is -7 dB, on both the original Scala and the Scala II, and yet the peak is not all that noticeable to every listener.  Maybe the boost in the mid-bass makes the lack of low bass less noticeable, to some listeners anyway.  Just my opinion.

[Chris A]

1 hour ago, Racer X said:

By uncolored I simply meant frequency response, flatness.  This is of course room dependent.

 

All loudspeakers have room-dependent SPL response below the room's Schroeder frequency (nominally 200 Hz for many/most home-sized listening rooms). The reason for the uneven response of the La Scala bass bin is two-fold:

1. its undersized horn mouths for the size of acoustic waves developed internally (an issue with most bifurcated "W" section bass bins), and
2. the La Scala bass bin is coupling to the room (i.e., boundary gain) due to its increased efficiency over direct radiating designs. 

If other (direct radiating) loudspeakers are so inefficient that they can't as effectively couple to the boundaries, then they suffer from not being able to effectively make use of that boundary gain.  PWK wrote an article discussing this physical phenomenon, advocating that any loudspeaker does better in a room corner, with suitable EQ to flatten its response again to lower overall bass distortion:  https://community.klipsch.com/applications/core/interface/file/attachment.php?id=66006

 

Chris

[Racer X]

Hmm, room corners.  While any speaker will do better in a room corner bass response and room coupling wise, it is seldom the best placement when considering a strong center image.  Of course PWK countered this with a center channel.  I experimented with this with using both LaScalas and Cornwalls together in a wall of sound.  I now favor the Heresy pair pulled about 4 feet away from the back wall and toed in 45 degrees and well far away from the side walls.

[Chris A]

7 minutes ago, Racer X said:

While any speaker will do better in a room corner bass response and room coupling wise, it is seldom the best placement when considering a strong center image.

 

Well, about 10 years ago, I created a thread on that subject:

Chris

[Racer X]

Thanks Chris for reposting, obviously I'm new to the forum and have not read any posts older than one year.  There is a lot to take in there, especially the argument for MOSFET amps over SET.  I can only relate what has worked or not worked for me in my room.  

[Racer X]

OK, I've reread your most informative repost, and I believe the main issue here is I'm dealing with small Heresy speakers in a medium size (20 x 20') room, while you are coming from large auditorium fully horn loaded speakers in a larger room.  In my youth I was entranced with the large horn speakers, but my room was small and I soon realized I listened at about a 90 db level.  While speakers with kick demo well, I do not believe listening levels above 100 db can be sustained for any period of time.  In my advancing years, I am now very happy with the smaller Heresy fed by an esoteric OTL tube amp.  Also, I grew tired of staring at huge speakers, really appreciate the size, performance ratio of the Heresy now.

 

Basically the point I was trying to make is speakers placed far apart (in corners) do not provide a strong center image (usually).

[Chris A]

8 hours ago, Racer X said:

...speakers placed far apart (in corners) do not provide a strong center image (usually).

 

Unless of course you're using K-402s...in which case, the entire front wall of the listening room becomes the soundstage (much like a good commercial cinema experience...imagine that...😉)  Here is an approach that dispenses with the large "W" section bass bin, producing a Cornwall-sized fully horn loaded loudspeaker, the K-402-MEH, which actually does not require a corner--but benefits greatly if placed there):

 

However, this thread is about Heresies, not La Scalas, Jubilees, or MEHs.  It's probably best to leave those other subjects alone in this thread.

 

8 hours ago, Racer X said:

In my youth I was entranced with the large horn speakers, but my room was small and I soon realized I listened at about a 90 db level.  While speakers with kick demo well, I do not believe listening levels above 100 db can be sustained for any period of time.

 

We typically listen mostly in the 65-75 dB range (average), and only get up to ~83-85 dB (average) during videos.  It's the sense of realism that is the real attraction.  There is no limitation to how soft or how loud.

 

Chris

[jcn3]

On 7/10/2021 at 8:35 AM, pcbiz said:

The 10 gauge wire sounds sooo much better.

 

hey there.  i'm curious where you got the terminations (spaces, etc.) for your wire -- i've only been able to find cheap zinc ones and am hoping for something better.  thx!

[pcbiz]

4 hours ago, jcn3 said:

 

hey there.  i'm curious where you got the terminations (spaces, etc.) for your wire -- i've only been able to find cheap zinc ones and am hoping for something better.  thx!

 

This is what I'm using now for my La Scalas:

 

https://douglasconnection.com/product/furutech-fp-209g-gold-plated-copper-small-spade/

 

https://www.vhaudio.com/furutech-ft-210.html

Edited February 8, 2022 by pcbiz

[babadono]

4 hours ago, jcn3 said:

 

hey there.  i'm curious where you got the terminations (spaces, etc.) for your wire -- i've only been able to find cheap zinc ones and am hoping for something better.  thx!

How's about PE (Parts Express)? They have gold plated spade terminals with little red/black booties

https://www.parts-express.com/Gold-Spade-8-AWG-6-2-Pair-095-670

Careful with what stud size you need. The ones I linked are #6 and work perfect with Klipsch original crossovers in La scala and KHorn. Also work perfct with ALK's stuff too. Don't know about Crites but would assume there good with those also.

[pcbiz]

1 hour ago, babadono said:

How's about PE (Parts Express)? They have gold plated spade terminals with little red/black booties

https://www.parts-express.com/Gold-Spade-8-AWG-6-2-Pair-095-670

Careful with what stud size you need. The ones I linked are #6 and work perfect with Klipsch original crossovers in La scala and KHorn. Also work perfct with ALK's stuff too. Don't know about Crites but would assume there good with those also.

 

Those would be fine. I just wanted pure copper, so I went with Furutech.