GIK vs. Real Traps?

Realtraps specializes in flexible membrane traps, which are not as broadband as "soft" traps but not as narrow band as rigid membranes (ie. 1/8" hardboard). Meaning, you can target upper bass/lower midrange with less effect on high frequencies.

Rigid fiberglass (Ready Traps) and mineral wool (GIK) are "soft" broadband traps.

GIK uses backing for support, while the others are, often, framed,

Relative effectiveness is relative to frequency, placement, coverage area, thickness ... Claims of effectiveness below 100 Hz is questionable on all commercial designs. When I needed to address a specific 90Hz problem, I went DIY, which wasn't cheap either.

Ngjockey:

That was a really helpful post, just the sort of info I was looking for! I'd be interested in hearing more about what you think of these traps efficacy for low bass issues, and what you might recommend.

Tholt,
The prices at ATS acoustics are very good. How effective are they as compared to GIK or Real Traps? Thanks for the info.

Testing labs do not publish data below 100 Hz because it's unreliable. Don't know where these companies are getting their data or what testing equipment they're using. Not saying they're untruthful, just informal. Don't know of any objective tests done between competing brands under identical conditions. What would be the purpose, other than misleading claims that don't reflect real installations?

As frequency drops, it becomes logarithmically difficult to produce and absorb. 50 Hz might have 4 times as much energy as 100 Hz. That means 4 times the relative thickness of a material or a different approach.

For a "soft" broadband trap, density and thickness become important to low frequency. Cotton, as layered in futon pads, works pretty well. Acoustic foam has been unfairly maligned as not being dense enough to absorb bass but it's intended to supplement a well designed room. Whatever works to address the problem.

A well made, 4' X 2', rigid membrane trap, using 1/8" hardboard seems to work well around 100 Hz (to my ears and fingertips). For 50 Hz, a similar trap would need to be 8' X 4' and probably use 1/4" membrane. Even drywall or panelling, not nailed down, can be a membrane. That's architectural scale and part of good studio and theatre design. An entire wall or ceiling could be a trap. I won't get into design of this type too much other than to say; caulking is your friend, solid mounting is essential, and the same type of material used in broadband traps is used for dampening inside the membrane trap.

Unfortunately, the region between 50 Hz and 100 Hz is a common problem for residential because of room dimensions and wavelength. Fortunately, our ears aren't as discriminating at these frequencies, unless you're an elephant.

I prefer GIK over Real Traps which are over priced and very, very ugly.