Altec 19 baffle Foam?

[hrtattckcity]

i keep seeing old posts mentioning a seller of Altec 19 baffle foam replacement but all the links seem to have gone cold.

Does anyone have a link to a current seller, or can someone take dimensions of their existing foam that I can draw up as a guide?

Thanks.

 

[hrtattckcity]

As soon as I posted some popped up for sale. I will update this thread with dimensions as a reference as I do not see any other documentation.

 

[hrtattckcity]

Foam showed up today.
Construction is a little sloppy. Some cuts run through where they should stop, and a lot of excess glue on the foam. Wish I would have had a resource to make my own.

 

[BillWojo]

Awesome that you posted the dimensions. Yea, I would be upset about sloppy workmanship to. I hope that it isn't obvious or I would contact the seller. I suspect that he/she may be reading this forum as well since they posted a set on ebay as soon as you talked about it.
Let us know if they make much of an audible difference.
Really glad these are coming along. Good to have another Altec guy in the area.

BillWojo

 

[toddalin]

View attachment 1436056
Foam showed up today.
Construction is a little sloppy. Some cuts run through where they should stop, and a lot of excess glue on the foam. Wish I would have had a resource to make my own.

Electric carving knife and a little practice works for foam. You could even make a "jig" to follow. Could also use a "hot wire"/"hot knife" and jig.

 

[hrtattckcity]

So...don’t use those dimensions I posted.
I took those when I opened the package and they are a pretty bad fit in my 19’s. You can see in the attached photos how they bulge out.

I’m going to try to return them and either go foamless or measure my altecs for a better fit.

I will update if I find a better solution—and would be eager to see photos or drawings ofanyone’s OEM foams.

 

[bowtie427ss]

I will update if I find a better solution—and would be eager to see photos or drawings ofanyone’s OEM foams.

Original foam disintegrated a couple/3 decades ago, it was very open cell, and apparently not very chemically stable.

The foam was all about cosmetics over function. For decades Altec damped baffle surfaces around the horn with loosely packed fiberglass which is a far more effective damping material than any foam.

The foam looks nice, and is a definite cosmetic improvement over fiberglass. But, it's at least a step or two backward from fiberglass in effective damping of reflected acoustic energy.

Consider using wool felt padding similar to, or the same as Altec used to damp the rear chambers of their compression drivers.

Some of you who still have decent HF hearing sensitivity may also notice an improvement by damping the inside surface of the horn's grill frame. IMO, there is as much HF reflection and diffraction going on there as there is from any part of the cabinet itself, yet you will seldom if ever see it mentioned or discussed.