Strengthening La Scala cabinet?

[Woofers and Tweeters]

42 minutes ago, Honeybadger said:

I personally wouldn't have another pair of LaScala's without braces and some version of the DJK port mod.

Yes, and new posters need to know who he was, then they can search and learn more. 

[Woofers and Tweeters]

2 hours ago, Dave A said:

Yes he did consider mid braces. On the forum there is a picture of him in his speaker tinkering room and behind and to the left of him is a La Scala with mid braces. Why simple fixes for problems were not implemented I don't know.

Yes

https://community.klipsch.com/index.php?/topic/170152-hooking-up-k-402-horns-to-commercial-la-scalas-bracing-the-bins/

[OO1]

14 hours ago, Dave MacKay said:

 

1. Laminate 1/4" Baltic Birch panels to the top, bottom, and sides (

 

Adding the 1/4 inch to the side wall eliminates the resonance , without the need of braces , and braces are also real ugly , they make  a Lascala look like a Peavey cab , so no wonder Klipsch avoided the idea all together-

 

in the 80's and 90's , on the Lascala Industrial rounded corner cabs , klipsch switched to a plywood that was slightly thicker than 3/4 inches and that eliminated the perceived resonance  , so  a stiffer cab , they now use 1 inch MDF , with 0 issues -

[pcbiz]

7 hours ago, RandyH said:

Adding the 1/4 inch to the side wall eliminates the resonance , without the need of braces , and braces are also real ugly , they make  a Lascala look like a Peavey cab , so no wonder Klipsch avoided the idea all together-

 

in the 80's and 90's , on the Lascala Industrial rounded corner cabs , klipsch switched to a plywood that was slightly thicker than 3/4 inches and that eliminated the perceived resonance  , so  a stiffer cab , they now use 1 inch MDF , with 0 issues -

Science! 🎵

[Marvel]

12 hours ago, Dave A said:

Yes he did consider mid braces. On the forum there is a picture of him in his speaker tinkering room and behind and to the left of him is a La Scala with mid braces. Why simple fixes for problems were not implemented I don't know.

I believe the braces weren't implemented due to the need for hand fitting. Modern techniques with CNC equipment  has increased the accuracy of the cuts and all that jazz.

[Dave A]

1 hour ago, Marvel said:

I believe the braces weren't implemented due to the need for hand fitting. Modern techniques with CNC equipment  has increased the accuracy of the cuts and all that jazz.

That is a problem easily solved. When I make my braces they do not extend into the rectangular section next to the doghouse but rather are shorter a bit than the depth of the angular section of the doghouse. Sliding the brace in until snug has worked on every one so far I have done as the angle from the doghouse point to sidewall is very consistent even in pre cnc days. Like other things though that no brace decision was made and the reasoning was not recorded and we will never know why.

[pcbiz]

27 minutes ago, Dave A said:

That is a problem easily solved. When I make my braces they do not extend into the rectangular section next to the doghouse but rather are shorter a bit than the depth of the angular section of the doghouse. Sliding the brace in until snug has worked on every one so far I have done as the angle from the doghouse point to sidewall is very consistent even in pre cnc days. Like other things though that no brace decision was made and the reasoning was not recorded and we will never know why.

I'm going to need those braces when I get  my La Scalas. 

[OO1]

PWK  favored a speaker with no visual bracing in 1963 ,   better build techniques and stiffening the cabinet were the work around  in later years , the new standard is 1 inch MDF for a no-braces  speaker  -

 

 

[CECAA850]

I like the look of the braces personally.  I also agree with Dave.  You can cut slightly shorter braces and theyll fit any cabinet.  The angles are all the same.

[Dave A]

7 hours ago, RandyH said:

PWK  favored a speaker with no visual bracing in 1963 ,   better build techniques and stiffening the cabinet were the work around  in later years , the new standard is 1 inch MDF for a no-braces  speaker  -

 

 

Actually looking at that cabinet it occurs to me that perhaps resonance was recognized as a problem early on. One side on the floor and the other braced with the mid-tweeter motorboard would have stopped resonance.  Butt ugly though and changes were made for cosmetics would be my guess. Hide the access panel and crossover and make it more finished looking.

[OO1]

,,,,,,

[billybob]

15 minutes ago, RandyH said:

I think you nailed it  -

No, he screwed it...

[billybob]

4 minutes ago, billybob said:

No, he screwed it...

Well maybe glued it but yeah.

 

Tattoo...

[dtr20]

Random thought, not sure if this had been brought up before. Could you just add quarter inch plywood on the sides, top, and bottom of the cabinets? This could be essentially reveneering the speakers while adding rigidity. If you miter the corners, this could look great with edge banding, just need to figure out the front.

[PrestonTom]

8 hours ago, dtr20 said:

Random thought, not sure if this had been brought up before. Could you just add quarter inch plywood on the sides, top, and bottom of the cabinets? This could be essentially reveneering the speakers while adding rigidity. If you miter the corners, this could look great with edge banding, just need to figure out the front.

In general and painting with a broad brush ...... If you are trying to reduce cabinet vibration,  adding braces is usually more effective then adding mass.

[Dave MacKay]

Thank-you to everyone who has contributed to this thread. 

 

There have been responses in favour of all 3 choices:

   1) do nothing

   2) add bracing to the interior of the bass bin

   3) laminate 1/4" panels to the exterior of the cabinet

However, there wasn't clarity about which choice is best.

 

Because I'm not sure my hearing is acute enough, or refined enough, to discern the resonance problem, doing nothing was appealing. Nevertheless, the resonance problem with the original La Scalas has been well documented. Since I'm in the midst of refurbishing the speakers, why not eliminate a problem if I can?

 

Adding braces to the bass bins was attractive in that it would be (relatively) simple and easily reversible, However, I was concerned that the braces might impair the sound, since they would consume a not insignificant volume in the bass bin. 

 

I'm inclined to proceed with laminating 1/4" panels to the sides, bottom, and top for these reasons:

- it may eliminate (and certainly won't worsen) the resonance problem

- at worst, it shouldn't impair the quality of the sound 

- In my opinion, it would be visually more appealing than adding braces

- the new panels should provide a good surface for veneering

I recognize that making a big speaker even larger does nothing for their WAF, and the modification might impair the value of the speakers if I ever want to sell them.

 

I'd be really interested to hear from those who disagree with my inclination, and especially from anyone who has laminated thin panels to their La Scalas and is willing to share what difference they felt it made.

 

[henry4841]

Sounds like a good plan to me. You are not going to enlarge the speakers that much using 1/4" panels. Go for it. 

[JMeader]

I did what you are planing for the same reasons, onli I use ½ inch MDF then veneer, I even put MDF in the area containing the Squaker and tweeter, top of dog house.

 

The results are a more refined sound, does nothing for base and I have found tilting the speakers up provides the best sound. Sound stage is slightly better and I have really enjoyed the difference

 

FYI I also updated all three drivers and crossover using Crites products. 

[CECAA850]

29 minutes ago, Dave MacKay said:

Thank-you to everyone who has contributed to this thread. 

 

There have been responses in favour of all 3 choices:

   1) do nothing

   2) add bracing to the interior of the bass bin

   3) laminate 1/4" panels to the exterior of the cabinet

However, there wasn't clarity about which choice is best.

 

Because I'm not sure my hearing is acute enough, or refined enough, to discern the resonance problem, doing nothing was appealing. Nevertheless, the resonance problem with the original La Scalas has been well documented. Since I'm in the midst of refurbishing the speakers, why not eliminate a problem if I can?

 

Adding braces to the bass bins was attractive in that it would be (relatively) simple and easily reversible, However, I was concerned that the braces might impair the sound, since they would consume a not insignificant volume in the bass bin. 

 

I'm inclined to proceed with laminating 1/4" panels to the sides, bottom, and top for these reasons:

- it may eliminate (and certainly won't worsen) the resonance problem

- at worst, it shouldn't impair the quality of the sound 

- In my opinion, it would be visually more appealing than adding braces

- the new panels should provide a good surface for veneering

I recognize that making a big speaker even larger does nothing for their WAF, and the modification might impair the value of the speakers if I ever want to sell them.

 

I'd be really interested to hear from those who disagree with my inclination, and especially from anyone who has laminated thin panels to their La Scalas and is willing to share what difference they felt it made.

 

Braces will absolutely not degrade the sound. Just the opposite. 

 

Play some bass heavy music while sitting in front of the bass bin.  Listen for a minute so that you are familiar with the sound.  Once you are, apply pressure to the sides.  You'll hear the benefit of braces. It's pretty obvious. 

[Bubo]

In this case, I am in the do nothing camp

at normal listening volumes, no need.

If they were screaming at a club or theater, brace away.

My two cents......