Insulation for Speakers

[GM]

Greets!

Yeah, they have an aggressive censoring program, so preview your messages to detect it and add dashes if you want your s***** to be seen: s-c-r-a-p-s.

GM

[GM]

Oh yeah, back on topic, I prefer fiberglass, but Miraflex R-25 works just as well and is fairly benign.

GM

[Steve Mac]

I've got 2 big bags of Acousta-Stuf I pulled out of the big transission lines I built a few years back. The stuff was expensive but it's nice and safe and works great. I have no idea, I should try to get rid of these bags, I don't know as I'll be using them for any project as large as that one.

[Sounder]

Thanks, Steve, Tenorman and GM.

I saw some bags of Acousta Stuff on eBay several weeks ago, before I knew that I would be needing stuffing. I know that it is very expensive but it is recommended over polyester. As I recall, it's crimped nylon fibers.

[Old Guy]

I use this stuff.

http://sweets.construction.com/mfg/20685/P29116.htm

Cuts easily with scissors. Has a rubber binder to prevent shedding, can be handled in shirtsleeves with no probs. Have used it since the '70's.

[Sounder]

Todd, the 11 cu ft is based on external measurements (48H x 23W x 18D) using 3/4 in red oak plywood. After the bracing (2x4s on corners, back and the "X" running front to back and side to side), it would be more like 10 cu ft, which is, I believe, the recommendation for the Iconic Vs.

As an alternative, I am also considering adding an "internal skin" of 3/4" plywood glued to the external skin but I may need a crane to move them. I suspect this is overkill. BTW, these are to house some new 604s from GPA.

I am also adding the usual 2.5 x 11 in port 3 in below the speaker port (see attached). Sound right?

John

[Sounder]

Thanks OG for the lead on the acoustic liner for ductworks. I will consider this for future projects.

In the meantime, I ordered some densified, 2" thick polyester batting (28"W x 9 yd L) from hiloftnw.com for $14.50 per 9 yd roll. I figure a couple rolls will give a 4" lining. Gene James (1-800-351-5687) from the company was very helpful, indicating that several others used this for speaker damping purposes. I'll let you know how it works out.

I appreciate everyones input. I learned a lot, as usual, from this group.

[Sounder]

I read (in Altec literature on how to construct UR own speakers) that batt lining (sheets) work better in ported (bass reflex) boxes than does loose stuffing, that works better in acoustic suspension (sealed speakers).

But, as you know, we often see ported speakers stuffed with loose fiber. My impression is that loose is OK as long as it is not so tight as to prevent the reinforcing wave from exiting the port. The amount of stuffing would be adjusted when you tune the port(s).

Now, I will wait for more experiences audiophiles to respond (and point out if I am wrong).

[GM]

http://web.archive.org/web/200210070...ces/fiberfill/

[valhallax]

ok..weve established the types of dampning material, but i need to know is the effects. i saw a link here that showed some 3182's in what appeared to be sonotubes..the tubes were losely stuffed with batting to the top. my question is, does this not reduced the internal volume of the cabs? i talked to a speaker tech at emminence and he said they also loosely stuff their cabs, full of pillow stuffing. all of my diy cabs have in the past just had the walls lined with insulation. pros and cons of each method appreciated