[John Casler]

As many know "trapping" LF wave energy can be effective and expensive.

I do not make any claims to the frequency range or effectiveness of some of my DIY tweaks, but have found they modify the sound to my liking.

I also don't claim that they will meet "ANY" aesthetic criteria unless you find a method to "spruce them up".

That disclaimer out of the way, I might offer a fun tweak to try for DIY Lower Frequency traps.

I have four LARGER Subwoofers and the shipping cartons (large cardboard boxes) are huge, and rigid, compared to normal cardboard boxes.

After examining other commercial and DIY traps, I thought I might experiment with these boxed as trapping devices.

I have also used RM40 (nice and tall and great for corners) boxes.

First I stuff the boxes with various materials.  Generally this is a mixture of tightly packed old clothing, bedding and more cardboard.  My thought here is to allow the LF energy to first be absorbed by the outer cardboard layer, and then what passes through will encounter both the internal carboard baffling and the packed clothing to further reduce the energy return.

I also (in an attempt to make these better looking) staple acoustic foam to the outside to also make them non reflective, and affect higher frequencies, and in some cases I pick up "airline" blankets (can be found at most Wallgrens or Savon Stores for a few dollars) and wrap and staple them to the exterior.

Point being, that these can be easily placed in the room corners and stacked to the ceiling if desired.  They can also be placed behind the listening areas, around the listening area or even (like I did) used to form a "listening chamber".

Obviously this is not a tweak for the "living room", but for a dedicated listening area it can be "huge" in its sonic benefits for pretty low $$ output.

Maybe some acoustics expert can offer how effective these "may or may not" be, and on what frequencies, but I can say that the results seem very good, for those on a budget who like to tweak.

I'm of the subjective opinion, that they are at least the equal of the "foam" type corner bass traps and possibly more.

Place them in all the corners and see for yourself.

As always this is a "for fun" tweak and is not intended to replace "professional products" of the same type.

[Ethan Winer]

John,

Great post. Yes, a cardboard box stuffed with "soft stuff" can indeed trap bass, especially if it's very large. And Yes, I actually tested this! You are correct that it's not as effective as purpose-built bass traps, and of course it looks like hell! But for someone on a budget it's definitely better than nothing.

--Ethan

[John Casler]

 of course it looks like hell!
--Ethan

                 

Thanks Ethan.  Hopefully someone will try these as a precursor to buying a more effective and "better looking" product from you.

See once you hear what they do, it is had to remove them.  So you either live with the "look", (actually when wrapped in the felt/cotton airline throw blankets they can be made to look OK) or they "upgrade" to the real thing, or should I say "Real Traps".

[ctviggen]

One of the cheapest and best bass traps is a helmholtz absorber (also called a resonator):

http://www.mhsoft.nl/Helmholtzabsorber.asp
http://www.audioholics.com/techtips/roomacoustics/Helmholtzresonatorabsorber2.php

Not as broad band as what you've done, John, but better at bass trapping.

[ricmon]

i did the same thing with my speaker boxes.  great minds?

[ctviggen]

Speaking of that, my SVS sub is basically a big tube with a smaller tube in it. Assuming the sub isn't on (which it isn't except for movies), I wonder if it provides any low frequency absorption?  Hmmm....If I can ever get ETF to work, I'll test that out.

[Joules]

Here's one - A box of 2' x 4' cieling tiles, wich is about a foot thick, wraped in carpet. You can even leave the plastic wraping on the "box". A box of fiber glass cieling tiles costs about 50 or 60 bucks. Take this carpet covered monolith and stack in corners as needed.  

[John Casler]

Joules,

Been meaning to tell you I love your avatar.  I am a big fan of the 21st Century Schizoid  Man.

[markC]

The Jon Risch "quick & dirty" bass trap is relatively inexpensive and works quite well in my room. It's basically just rolls of fiberglass insulation stacked and taped together and covered in burlap or grille cloth. Grille cloth looks nicer, but costs a lot more than burlap. I built 4 x 4' in burlap for about $150.

[Joules]

- thanks -

[warnerwh]

Yes, the Jon Risch quick and dirty traps are a good way to go. Three rolls of fiberglass taped together. Then a couple of wood endcaps cut to size so you have something to staple the burlap to. Look ok and work well.

 Jon Risch's ASC clone is also effective.  You can also get a large package of fiberglass that comes in a plastic bag that is about 4' tall and 14-15 inches thick. I have one hiding behind a 2'x4'x3.5" thick trap I made.  No way would Cheryl allow any of this stuff outside of my listening room though.

[markC]

Yes, the Jon Risch quick and dirty traps are a good way to go. Three rolls of fiberglass taped together. Then a couple of wood endcaps cut to size so you have something to staple the burlap to. Look ok and work well.

 Jon Risch's ASC clone is also effective.  You can also get a large package of fiberglass that comes in a plastic bag that is about 4' tall and 14-15 inches thick. I have one hiding behind a 2'x4'x3.5" thick trap I made.  No way would Cheryl allow any of this stuff outside of my listening room though.

No kidding! Judy gives me enough reminders about how I have turned our rec room into a listening room. She refers to it as my "hole". ...."I think I'll listen to some music tonight-Yea go to your hole, but please don't make me have to crank the tv volume".

[Glenn K]

Yes, the Jon Risch quick and dirty traps are a good way to go. Three rolls of fiberglass taped together. Then a couple of wood endcaps cut to size so you have something to staple the burlap to. Look ok and work well.

 Jon Risch's ASC clone is also effective.  You can also get a large package of fiberglass that comes in a plastic bag that is about 4' tall and 14-15 inches thick. I have one hiding behind a 2'x4'x3.5" thick trap I made.  No way would Cheryl allow any of this stuff outside of my listening room though.

Not sure if this is the same thing, but get the fluffy fiberglass in the rolls and stack it in corners, floor to ceiling (leave them in plastic bags).. Make frames in front of it with 1x2's and our favorite fabric.. Works pretty well..

Glenn