I'm in the process of building a fairly large number of acoustic panels and wanted to share a couple of resources I've found locally in Columbus, Ohio.
Capitol Drywall Construction http://branches.lwsupply.com/capitol-dr ... 43222.html stocks 3" Roxul AFB and an 8 sheet pack of 24"x48" is currently priced at $33. They also carry an appropriate spray adhesive, Nashua 357, at about $6/can which is somewhat cheaper than 3M 77 or comparable products I've found at the local home centers.
Central Ohio Bag and Burlap https://www.centralohiobagandburlap.com/ is an industrial supplier of bulk burlap and related products. They sell 25ft x 60" sheets of raw 10oz construction burlap for about $12 which are wide enough to wrap both sides of a 2'x4' panel horizontally and is a more efficient use of material than say the typical 48" width of burlap from Jo-Ann Fabrics which would require wrapping vertically and generate a lot of waste fabric. I was able to wrap both sides of four 2'x4' panels with one of these sheets and the cost worked out to about $3 per panel. If you have a large project they can sell you rolls of up to 300 yards. I'd also mention that the 10oz burlap is a substantially stronger material than the burlap I tried from Jo-Ann Fabrics.
With these resources I've got a completed 2'x4' panel coming in at about $14 including tax.
Columbus, Ohio resources
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