LaScala restoration and Driver placement

[AudioBuff123]

I have owned a pair of LaScala's since the late 70's.  They were manufactured in 1975 and 1976 based on how I understand the serial numbers to work (5N132 and 6P738).

I used them to help me pay for college (used them for DJing).  For the last number of decades, they have been unused and in various storage locations.  I recently retired and am in the process of cleaning them up and repairing a lot of dings and scratches and delamination of some of the birch veneer.

 

As I was doing that, I began to wonder about the placement of the tweeter and squawker horns behind that 3/4" plywood front panel. The openings are basically rectangular openings a bit smaller then the horns.   My question to the audiophiles out there is if the sonic characteristics would be better to mount the horns on the surface of the front panel rather then behind the plywood (ignoring how you would do that for a minute).  It would seem that the unsmooth transition of the wood stepping in front the horn opening would have an affect on the sound.

 

Of course I don't have much of a clue about these things - and I don't have any program or anything to model it.  But I am hoping it is something that may have been discussed before or that folks have considered.  Please let me know your thoughts.  Thank you.

[wuzzzer]

That topic has been discussed before.  There’s no doubt that what you’re describing will alter the sound from the horns, how much though is the question.

[AudioBuff123]

Thank you Wuzzer.  I'm sure the topic has been reviewed before.  I don't seem to be able to figure out how to do a search to come up with the right threads.

When you mention 'it will alter the sound' - do you mean that in a good way?

[opnly bafld]

.

[Dale Stevens]

???

[wuzzzer]

5 hours ago, AudioBuff123 said:

Thank you Wuzzer.  I'm sure the topic has been reviewed before.  I don't seem to be able to figure out how to do a search to come up with the right threads.

When you mention 'it will alter the sound' - do you mean that in a good way?

The only thing I can see it doing is making the dispersion coming from the horns narrower than if the horns were front mounted.  How audible it actually is is beyond me.

[Woofers and Tweeters]

11 hours ago, AudioBuff123 said:

I began to wonder about the placement of the tweeter and squawker horns behind that 3/4" plywood front panel.

That would help the time alignment, but not enough to help to improve the sound. 
Here is one thread about that change

Damping (not dampening) the K400 will make a difference worth doing. Lots of threads about that.

Refreshing the crossovers would be the first and most noticeable thing to do, replacing the tweeter with a SMAHL is the larges improvement, but the others cost less.

[opnly bafld]

.

[Woofers and Tweeters]

8 minutes ago, 82 Cornwalls said:

 

New ones are mounted on the front for a reason and if you leave them on the back you will probably keep second guessing yourself.

 

Klipsch Cornwall Time Line

"The Cornwall II is introduced featuring front mounted drivers to reduce baffle induced diffraction effects."

They moved the Heresy mounts to the front too.

IMHO, the largest improvement in sound quality had nothing to do with moving the horns. Replacing the cowbell-sounding metal horns with a plastic (composite) was what helped. 

[opnly bafld]

.

[opnly bafld]

.

[CWOReilly]

9 hours ago, Woofers and Tweeters said:

They moved the Heresy mounts to the front too.

IMHO, the largest improvement in sound quality had nothing to do with moving the horns. Replacing the cowbell-sounding metal horns with a plastic (composite) was what helped. 

But the plastic horns were moved to the front. I’d say a combination of the two made the improvement. 

[Marvel]

20 hours ago, Woofers and Tweeters said:

That would help the time alignment, but not enough to help to improve the sound. 

Moving the horns to the front of the baffle actually worsens the alignment. The tweeter would need to be farther back to align with the mid horn and it would need to be further back to align with the woofer. The tweeter/mid will be more apparent.

[OO1]

On 5/20/2024 at 9:35 AM, AudioBuff123 said:

 My question to the audiophiles out there is if the sonic characteristics would be better to mount the horns on the surface of the front panel rather then behind the plywood (ignoring how you would do that for a minute). 

yes ,  it would sound more open  , however the screws + the outer section of the horns would be apparent requiring a set of grilles to hide the K-400 casting  

[Woofers and Tweeters]

3 hours ago, Marvel said:

Moving the horns to the front of the baffle actually worsens the alignment. The tweeter would need to be farther back to align with the mid horn and it would need to be further back to align with the woofer. The tweeter/mid will be more apparent.

I totally agree and I did not mean to advocate moving the highs forward. 

 

 

23 hours ago, Woofers and Tweeters said:

On 5/20/2024 at 9:35 AM, AudioBuff123 said:

I began to wonder about the placement of the tweeter and squawker horns behind that 3/4" plywood front panel.

That would help the time alignment, but not enough to help to improve the sound. 
Here is one thread about that change

To be clear: Placing the highs towards the rear will help, but the placement has to be more than fractions of one inch. 

[Woofers and Tweeters]

14 hours ago, CWOReilly said:

But the plastic horns were moved to the front. I’d say a combination of the two made the improvement. 

I will bet dinner (your choice where) that it was for reasons other than sound improvement. 

[CWOReilly]

7 hours ago, Woofers and Tweeters said:

I will bet dinner (your choice where) that it was for reasons other than sound improvement. 

Well of course. I can think of several.