John Sayers' Recording Studio Design Forum Archive

I am Al Burnstien I found out about this spot from TapeOP.com I live in sacramento CA and i have been looking for Owens Corning 703/705 ridged fiberglass for ever; dose it still exist?

what suff can I buy at Home Depot that will work for spot treatment?

sould I make pannel absorbers insted?

how do you toon a helmholtz resonator i.e. how much air space to a given Hz?

is there a place that has the absorption coefficient values for stuff we can buy at home depot and the like?

are there any cheep ways to float a floor?

Al, first let me welcome you to the site - second, you've covered more questions about things other than materials for this section, things that would be better answered in the Construction forum. However, since I don't have moderator status on this forum, we'll have to leave it here for now.

I'll cover your questions in order -

Owens Corning stuff does exist, however OC themselves apparently have no interest in selling to private individuals, nor do places like Home Depot sell the particular OC products that we can use, since they are considered "Industrial" or "Commercial" products. So far, about the only way to find the 700 series of rigid fiberglas insulation is to try all your local Commercial drywall/insulation contractors, and hope to find one that will deal with individuals. It helps to be friendly but persistent, and to call everyone in the Yellow pages that claims to do either drywall, insulation, or anything commercial. We've been trying since this site came together to find alternatives, and all of them have similar restrictions.

When anyone DOES find sources for these products (same with things like acoustic caulk/sealant, etc) we ask that they post the sources here in this forum, so others might get luckier.

Nothing you find at Home Depot (at least the one in MY area) has any practical use in acoustics - their insulations are mostly loose fiberglas batts, which are limited in effect, their foam insulations are all Closed cell, which doesn't work for absorption, if they handle Sill Seal, it can be used to bed wall frames, and of course their building materials (sheet rock, lumber, etc) are fine for construction.

Panel absorbers will work with the fluffy fiberglas insulation, as long as you use something like chicken wire fastened across the inside to keep the insulation from touching the front panel -

Tuning a Helmholz can be done with the calculator located here -

http://www.saecollege.de/reference_mate ... mholtz.xls

Or, if you have Excel on your machine and want your own copy (I've modified mine to include some other info) you can Right click on Helmholtz Calculator on the sidebar, and choose "Save Target As", and save the spreadsheet to your hard drive. You'll need to be familiar with the metric system - I added a group of cells to my version that show several different examples right on the sheet.

The biggest single source of absorption coefficients I've come across is also an Excel spreadsheet; you WILL need Excel on your machine to use it as it only works as a download.

http://www.wsdg.com/resources/resour.php?SL=te&BL=6

Floating floors - One way that's been used by several people I've talked to, is to go to a Tack shop or farm supply and ask for horse trailer mats - they are about 4 x 6 feet, and almost 1" thick (thicker than necessary for floating floors, but still usable) - you can cut them into "pucks" with a razor knife (get the heavy duty kind, and several blades)

There are a few threads in the Construction forum on floating floors, check them out for construction ideas.

I'm off to work for now, I hope this helped... Steve

i'm in so.cal. and my home depot has 2 inch thick rigid insulation. is that the same stuff? or close to it? it looks like it would work. check it out at www.jm.com

sick

In Northern California call Calply:

contact Eric Hanson - Branch manager San Francisco office
1455 Custer Avenue
San Francisco, CA 94124
(415) 282-0711

Tell him 'Chung from Novo group referred you over about sound isolation related materials.

They sell Thermafiber SAFB 2.5 lbs/square foot. I just ordered a couple thousand square feet

And they carry Certainteed Commercial insulation:

ask for CB300 unfaced rigid insulation for bass traps and such. 3 lbs/square foot. NRC 1.05

They also will order Owens Corning 703 in 2", but 4" requires a minimum order to do a run. . . your volume probably is not big enough for that.

They carry USG acoustical caulking, drywall, steel framing members of all types.

Hope that helps,
'Chung

(Note:) Before contacting Calply, please understand and know what you're ordering. They are not sound isolation or acoustics specialists and will not be able to answer a lot of "will this work for sound isolation" or "will this absorb this frequency" type of quesitions. They are commerical building products suppliers. Do the research on the product you're after or a set of products that will work for you on this forum and from manufacturer's websites. Then, call them to see what they have in stock and are able to get when you need to order.

For floating floors you'll need to have either a good idea or a good estimation of your loads.

Look for material weights on the internet. Think about how you're constructing your walls (if there are going to be walls bearing down on your floated floor or not.. . . ) Next, figure out how much all the stuff in the room will weigh including people. Make a maximum and a minimum weight. . . make sure you include the weight of the floating floor itself.

Armed with this information, check

http://www.mason-ind.com/

look in their architectural engineering menu under EAFM elastomeric floor mounts.

http://www.mason-ind.com/eafm_mounts.htm

Look for the different profiles of floor floating mounts, think about your assembly. . . look at the rated load ranges. Figure out your isolator spacing under the floor and calculate the loads per mount. Look at the natural frequency of the mounts as they are used within our load range (lower frequency is better) preferrably lower than the lowest sound that's going to be generated in the room. Tweek your spacing to load your mounts optimally. . .

If it turns out Durometer 60 isolators work well for you, consider finding an alternate source of EPDM sheet material and cut that into strips to use as isolators to save some money.

Other than finding a source of rubber of the correct durometer, the Mason pucks were the most economic solution for me. The Aurolex U-boats are also pretty reasonable, but they're Durometer 50 I believe. . .no other option. . . and they have not had their assemblies tested.

-'Chung