homeade bass tube traps

  • Thread starter Thread starter Executivos
  • Start date Start date
E

Executivos

New member
I've seen a few websites with directions for making bass tube traps for corners. One is using 12" diameter 1" thick fiberglass pipe insulation, the other using some kind of fencing/fabric netting or something.

The quotes I got for the pipe route were too much (about $30 per 3 foot section of insulation, when the website says about $5)

My question is....is the air-tightness what makes this effective?

I saw concrete tubes at home depot for under 5 dollars. If I filled one with fiberglass and used liquid nails to glue wood circles on the end of it, will it work allright? Or does the fiberglass side of the tube help in another way?


BTW, layed the floated neoprene floor today....VERY easy to do, only took about 2 hours, and it came out GREAT. pictures coming soon
 
Have you checked the prices for the real thing? I bet that little 12"'er would run you well over $200$

If you have trouble with standing waves, you will be blown away by what they do. Don't bother messing with the design, just build it!! BTW, yes they have to be airtight.
 
Anyone got any figures on what they do?? ....they look impressive but what do they actually do??

cheers
John
 
I just looked at Mbranes second link. Those tubes look like a lot of work ( slow and dirty) to build compared to building them with the rigid fiberglass tubes. the fiberglass tubes need no internal support structure. Some specs can be found at

www.tubetrap.com

follow the links for tube trap to find the specs.

here are the plans for the DIY version

http://ic.net/~jtgale/diy2.htm

I've got 6 of them. 12 inch and 16 inch.
 
Hey guys, what if I get a regular water pipe (plastic, PVC) fill it with rockwool and cover it with fabric???
 
I belive the reason tube traps work is because of the pressure difference between the inside of the tube and the outside. Once the rigid insulation tube is sealed top and bottom the pressure difference (slight as it may be) is enough so that a low frequency wave front trys to equalise the difference. The insulation absorbs most of this energy and reduces those frequencies.

If the trap were made of a solid tube like a sonor tube or PVC pipe, the sound wave could never equalise the pressure difference and would just reflect. But a sonor tube (concrete form) with holes cut in it and lined/covered with insulation would probably work somewhat.

Cheers
Kevin.
 
longsoughtfor said:
I belive the reason tube traps work is because of the pressure difference between the inside of the tube and the outside. Once the rigid insulation tube is sealed top and bottom the pressure difference (slight as it may be) is enough so that a low frequency wave front trys to equalise the difference. The insulation absorbs most of this energy and reduces those frequencies.

If the trap were made of a solid tube like a sonor tube or PVC pipe, the sound wave could never equalise the pressure difference and would just reflect. But a sonor tube (concrete form) with holes cut in it and lined/covered with insulation would probably work somewhat.

Cheers
Kevin.
Click to expand...

what about a cardboard tube (made to fill with concrete, but empty, or maybe filled with fiberglass? It's not a solid air tight plastic like pvc, but somewhere in the middle. Am I better off searching for a cheaper place to buy the pipe covering?
 
Executivos,

I think that's what Kevin meant by sonar tube. Check out this link, which I got from a post by Mbrane up higher. These do not seem all that hard or expensive to make, just a little time consuming.

Now that I saw these pictures, I understand the concept better.

Bushice
Here's the direct link :

http://www.geocities.com/jonrisch/basstrap.htm
 
Last edited:
Does anybody knows how to calculate the diameter based in an specific frequency ( the one we want to atenuate) ?. There's lot of specification on how to build it but it doesn't work in my case. thanks
 
^^^ This thread is full of misinformation, so best to pretend it doesn't exist. :D

You'll get the best results with thick flat panels straddling the corners.

--Ethan
 
Using a sealed box or pipe, one in essence is creating a diaphragmatic absorber. The surface density, air space depth of cavity, internal cabinet fill material, and construction methodology are critical to achieving the unit's resonant frequency. Low frequency waves do not care about or react to air holes in any absorber. This is the domain of middle and high frequency absorption, not low frequency pressure management. Low frequency waves will pass right through any diaphragmatic absorber. What we hope for in our designs is to lower the waves energy level. Total low frequency absorption can never be really realized. It is like a chronic disease, all we can do is pressure management and drop its levels so its involvement in our mix goes from nuisance to exceptable.

Regards,

Mike
 
You must log in or register to reply here.
Back
Top