Midrange experiment with Auto sound panel deadener and high density acoustic felt..

[Remlab]

I’m doing this with all with woodworking tools, so pure aluminum was the only option. Alloys need not apply

 

[Remlab]

These are the blanks I started with.

 

[Remlab]

In the end, the drivers will be decoupled from the baffle(including the driver mounting bolts), and the constrained layer damped baffle will be decoupled from the cabinet (including the baffle mounting bolts), by using relatively high durometer rubber washers and where the baffle meets the cabinet, sorbothane gaskets.

 

[cracked case]

On three sets of speakers I've made I've held on the front baffle ( against a soft gasket ) by tension springs. Works quite well.

 

[Remlab]

About twenty five years ago, I went through my audio mad scientist phase. I'm still amazed about what my wife let me get away with in our living room. Eventually she put a stop to it, so now everything I do has to go through the WAF filter. It needs to be aesthetically pleasing or the project is dead in its tracks

 

[Remlab]

Some interesting articles out there on the viscoelastic properties of leather. I’ll have the perfect amount left after covering the baffles, so I’ll try that too.

 

[Remlab]

The mid bass itself has sculpted edges for top mounting, so it will be mounted to the leather on the baffle, which will obviously act as the gasket. I’ll take the 4” midbass as low as distortion measurements will allow. Probably around .5% at 90db/1m

 

[Remlab]

Chamfering wasn’t perfect, but it’ll work lopsided look is just from the camera angle

 

[Remlab]

With driver..

 

[Remlab]

In order to get the high density acoustic felt behind the vertically aligned cabinet brace, I had to cut a large hole in the back of the speaker, which obviously required more 1/4” aluminum Plates as covers to match the fronts.

 

[Remlab]

I decided to go with 1/8” thick, 40 durometer sorbothane as the constrained layer. $90.00 for two 12” x 12” sheets. Ouch!

 

[Remlab]

Performance - Controlling Shock & Vibration | Sorbothane

 

[cracked case]

Chamfering wasn’t perfect, but it’ll work lopsided look is just from the camera angle

You did that with woodworking tools? I've worked with leather for 30 years, I'm not sure it's as good as cork but I use hard 1/4 inch thick ( ox hide ) sole leather, softer stuff might be much better, pigs belly wouldn't be to bad. I'll be glad when they're finished and you can give your impressions on how they sound.

 

[Remlab]

Only after I was assured by the seller that yes, the 1100 series aluminum could be machined with woodworking tools. Very soft compared to other aluminum alloys.

 

[Remlab]

You did that with woodworking tools? I've worked with leather for 30 years, I'm not sure it's as good as cork but I use hard 1/4 inch thick ( ox hide ) sole leather, softer stuff might be much better, pigs belly wouldn't be to bad. I'll be glad when they're finished and you can give your impressions on how they sound.

After doing a few experiments with the leather, I decided it would be suboptimal for what I'm trying to achieve with CLD, so sorbothane it will be. I'll still use it on the front though.

 

[Remlab]

First speaker to ever use constrained layer damping, with a patent(now expired) issued to the designer/Sony
Sony ES SS-M9 loudspeaker | Stereophile.com

US5949033A - Constrained layer damped loudspeaker enclosure
- Google Patents

 

[Remlab]

Sony's second attempt with CLD with what looks to be the same cabinet style. The cabinet sidewall resonance measurements are pretty extraordinary..


Sony ES SS-M9ED loudspeaker | Stereophile.com


interesting supertweeter mount..

SONY SS-M9ED VERY RARE Audiophile Speakers Photo #2590930 - US Audio Mart

 

[Remlab]

Leather baffle test fit. Tweeter screws Are rusted a little bit. Needs painting.

 

[krivium]

It look nice!
I'm curious of outcome of your project. Thank you sharing it.

 

[cracked case]

I presumed that experiments looked ruff and ready ( mine do! ), but that looks well cool.