# Mostly Frameless Bass Traps



## johnr (Jan 6, 2007)

I just completed the bulk of my planned bass traps. I wanted to minimize the framing but needed to suspend many of them in my basement.

I used Johns Manville 814 (3pcf (48kg/m3)) semi-rigid fiberglass 2" thick from my local SPI location. All the panels so far are 4" thick overall.

Fabric is Dazian Celtic Cloth:

http://www.dazian.com/cgi-bin/page.pl?action=show_style&style_id=161&group_id=

Nice people, but if you do the order over the phone make sure you specify all aspects of the order (color, width, single piece, etc). If there are any extra fees for splitting the material (from their wider offering) find that out first also.

A picture of the frame. The frame is on the top of the panel only:









The L channel material I had on hand from the ceiling work I did in another room. It is ordered from here:

http://www.kensa.com/order.htm

Pieces are cut and riveted together. The assembly was then glued to the fiberglass panels (which where previously joined together with a small amount of glue). Here is the glue I used:

http://www.loctiteproducts.com/p/pl...remium-Polyurethane-Construction-Adhesive.htm

This was also left over from another project but I kept purchasing it to complete the bass traps.

The eye bolts screw into J-nuts. I was able to find some heavy duty ones. They are not like the ones available in the big box stores around me. I got them from a local hardware store.

Fabric is wrapped package style. On the ends before folding I cut the extra material that wasn't needed. Spray adhesive was used for the sides and back. Hot glue was used for the ends.

Mounting to walls was done a couple ways in my case but I am sure that will be application specific. Along the sides I used aluminum rod cantilevered into to space so I can slide them from flush to the wall to out enough to have a 4" air gap.

Here is one side of the space. Screen is not up yet (should arrive tomorrow):








Ceiling tiles were the cheapest black fiberglass tiles I can find. I wanted acoustically transparent tiles as ceiling is mostly joists filled loose with pink fiberglass. Perimeter joists are filled with Roxul Comfort Batt.

I will separately post acoustic results of treatments but will say decay time is pretty well reduced and sound is much better overall.


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## ALMFamily (Oct 19, 2011)

Nicely done John! :T Can't wait to see pics with the screen up!:T


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## Prof. (Oct 20, 2006)

Why did you need to suspend your bass traps? Ideally they should be floor to ceiling and for that type of trap, 6" thick panels..


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## johnr (Jan 6, 2007)

Prof. said:


> Why did you need to suspend your bass traps? Ideally they should be floor to ceiling and for that type of trap, 6" thick panels..


From what I have read floor to ceiling is not the prime directive but maximizing corner coverage is. Since corners extend vertically and horizontally (including tri-corners) this should be considered. It felt like with not a lot of extra material initially I maximized corner coverage. For example, the extra 2 linear feet of traps along side wall allowed me to cover 4 feet of floor-wall corner. The 2x2 chunk angled "shorted" the wall-to-wall corner but increased coverage of the tri-corner. With the modules I could probably test different configurations at some point.

As far as thickness 4" seemed like a reasonable compromise but yes, for that density material I could have gone 6" and improved absorption.


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