[bgewaudio]

Here is my idea,

I was thinking of building a bass trap that would consist of a sono tube (stiff cardboard like cylindar used for making concrete pillars) approximately 18" diameter, filling it with R12 wall insulation, then wrapping the outside with a ridgid fibreglass insulation and then wrapping that with a transparent fabric. Could this work?

[PaulHilgeman]

Here is my idea,

I was thinking of building a bass trap that would consist of a sono tube (stiff cardboard like cylindar used for making concrete pillars) approximately 18" diameter, filling it with R12 wall insulation, then wrapping the outside with a ridgid fibreglass insulation and then wrapping that with a transparent fabric. Could this work?

Well, it might be hard to wrap the rigid fiberglass, and stuffing the inside wouldnt do too much.

What I have done that works really well is to buy a few wicker trunks.  I bought a few at Target a few years ago for a room that was a bit hard to deal with.  I filled these with fiberglass insulation and played with locations.  The largest trunk was 2.5 x 3.5 x 2 (HWD) feet, and then two smaller ones.  These made a good difference, looked good and were cheap.

-Paul

[bgewaudio]

Thanks Paul, anything else to try?

[Ethan Winer]

> I was thinking of building a bass trap that would consist of a sono tube (stiff cardboard like cylindar used for making concrete pillars) approximately 18" diameter, filling it with R12 wall insulation, then wrapping the outside with a ridgid fibreglass insulation and then wrapping that with a transparent fabric. Could this work? <

Every month or so someone suggests something like that.

Unfortunately, it's not a great idea for a variety of reasons.

--Ethan

[bgewaudio]

Ethan, could you describe these reasons?...........PM?

[Ethan Winer]

> could you describe these reasons? <

Main reason: That type of cardboard is too thick and rigid to pass bass into the insulation inside.

[brj]

I would think the fiberglass/rockwool pipe insulation "tubes" would be an easily constructed option.  This is a path that I've been considering, with the following variables:

1) Taking the scrim off of one half of the tube and playing with how the tubes are faced into the room
2) How to fill the tubes, with the following thoughts:

• Completely hollow
• Filled with pink fiberglass wall insulation/acoustic cotton/etc.
• Additional layers of pipe insulation (no scrim) with an air-gap between layers
• Additional layers of pipe insulation (no scrim) without an air-gap between layers

The pipe insulation can be had in mutliple diameters.  The appropriate diameter would be selected according to the bass frequencies that you want to tame.

[bgewaudio]

The only reason I decided to use the latter approach with the sono tube was givin the nature of low frequencies (longer wavelengths), I thought it would make sense to throw some more ridgid materials in there in hope lower frequencies would pass through and then become much harder to exit.

[MaxCast]

I wish this idea would work too.  I've read enough of Ethan's responses to not research further....but what if we cut holes in the tubes Ethan??   Lots of holes.
I don't have time to mess with the chicken wire tube thingies.

[bgewaudio]

I second that!

[brj]

I don't have time to mess with the chicken wire tube thingies.

Thus the pipe - insulation idea... no holes needed... even less work!

This approach has come up before, although I confess that I don't remember people reporting results.  I'll have to go back and reread it myself.

[srlaudio]

The ASC Tube traps Do work as a bass trap.  Their basic construction is a rigid fiberglass tube (no pegboard in sight), fabric wrapped, filled with Dacron (pillow material).  Leave out the "limp membrane", a 3 mil piece of plastic to give a weak form of diffusion, and you end up with a reasonably effective bass trap.  The larger diameter tubes moves the center frequency downward.  (So use a stack of different diameters to broaden the "q".)  Incidentally, The ASC products are covered with Guilford of Maine grill material.  This is the professional standard of high quality acoustically transparent material.  We use the same on all our products.

[klh]

Allen... you should get a circle to promote your product. Am I wrong or is this circle one for general knowledge and not self promotion?

[srlaudio]

I don't make or sell ASC products.  I was just pointing out that their design is effective (it is patented) and can be copied by a DIY'er.  A DIY'er can also buy Guilford of Maine.  There must be a reason that all of the top acoustical manufacturers and designers use it. 

[MaxCast]

Allen... you should get a circle to promote your product. Am I wrong or is this circle one for general knowledge and not self promotion?

klh, manufacturers are encouraged to participate in any threads at AC.  A BRIEF one time shot about their products is acceptable for the consumer to research further if they desire.  Or if directly asked from a consumer.  I see Allens response as more as a help than a sell.

[MaxCast]

brj, thanks for the thread link.

We need someone to build 4 of these 18 inchers floor to ceiling and do EFT measurements before and after.

[brj]

brj, thanks for the thread link.

No problem, MC.  One of the links worth pulling out of that AC thread was a pipe insulation based tube trap recipe. 

We need someone to build 4 of these 18 inchers floor to ceiling and do EFT measurements before and after.

Well, I have a measurement setup out for calibration at the moment and plan to measure my room once I get it back.  I would also like to build a couple of 4 foot tall traps at some point, and will also take measurements once completed.  I don't expect it to happen right away, but I'll post what I see when I get there.

[klh]

OK... point well taken. I wan't sure if he crossed the boundry... and I respect your opinion. BTW, I do think Allen's products are impressive. The fact that this circle is mostly for sharing knowledge as opposed to excessive self promotion is one of the many reasons I frequent it regularly. That and the fine people associated with it .

[MaxCast]

OK... point well taken. I wan't sure if he crossed the boundry... and I respect your opinion. BTW, I do think Allen's products are impressive. The fact that this circle is mostly for sharing knowledge as opposed to excessive self promotion is one of the many reasons I frequent it regularly. That and the fine people associated with it .

No problem, klh.  Allen is new.  I'm sure all will be well.
Have a great weekend, it's almost quittin' time.

[klh]

Lucky you! I'm on the west coast so it's only lunch time .