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Thoughts on these DIY bass traps?

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Thoughts on these DIY bass traps?

Postby Urumiko » Fri Feb 24, 2017 3:22 pm

I will in the not too distant future be soundproofing a room with a really small budget.
The instant thought was to buy the sheapest accoustic foam possible from e-bay but i understand this stuff is often not up to the job especially where pass traps are concerned.

I saw this DIY vid for bass traps and really liked the aproach, I 'm tempted to do something similar and would value opinions.comments?

https://www.youtube.com/watch?v=dZV-gxVpkGk

I also was considering a coating of spray adhesive just as an aditional layer of protection agianst stray particles. What do you think?

I was still planning to use cheap foam pannels glued to cardboard sheets and then hung on the walls as well. Does this sound apropriate?
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Re: Thoughts on these DIY bass traps?

Postby Wonks » Fri Feb 24, 2017 3:37 pm

Not good traps at all and certainly not bass traps. Only really effective in the video because he's putting material over hard walls, and making them less reflective. This is not bass trapping.

Bass trapping needs a lot of absorbing material, normally rockwool or fibreglass, and put in corners (held away from the walls) where the worst bass problems occur.

There are loads of threads on bass traps here, plus articles in SOS as well, so it's really worth doing a search about building your own traps and panels.

You can spray a dilute PVA mixture onto the face of the absorbing (not covering) material, but you need to ensure that it doesn't close up the pores, as that will simply make the absorber reflective and almost useless.
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Re: Thoughts on these DIY bass traps?

Postby Urumiko » Fri Feb 24, 2017 3:59 pm

Wonks wrote:Not good traps at all and certainly not bass traps. Only really effective in the video because he's putting material over hard walls, and making them less reflective. This is not bass trapping.

Bass trapping needs a lot of absorbing material, normally rockwool or fibreglass, and put in corners (held away from the walls) where the worst bass problems occur.

There are loads of threads on bass traps here, plus articles in SOS as well, so it's really worth doing a search about building your own traps and panels.

You can spray a dilute PVA mixture onto the face of the absorbing (not covering) material, but you need to ensure that it doesn't close up the pores, as that will simply make the absorber reflective and almost useless.

Ah yes, Schoolboy error, I'm reading some articles now, So the term bass trap is being mis used here. The do seem like they might be attractive alternatives to foam for general sound absorption to stop reflections though? perhaps even have a layer of fiberglass on the bottom and a layer of foam on the top.
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Re: Thoughts on these DIY bass traps?

Postby Wonks » Fri Feb 24, 2017 4:20 pm

You really don't want a relatively hard, solid reflective foil in the middle for broadband absorbers. The whole idea is to have an open pore material that lets sound waves penetrate the material and absorb the energy as they penetrate. If they hit a barrier, then most of that energy will reflect back again, making half of the fibreglass (or more typically rockwool in the UK) do almost nothing. Some bass wavelengths might make the foil move a bit and so pass on a small amount of the bass energy, but not a lot.

You really want the sound to pass through the full depth of the absorber, then hit the wall and be reflected back through the absorber again to make it even more effective. Because standing waves have nodes (zero movement) at the flat surfaces like walls, the absorber needs to be moved away from the walls by as much as possible, so that it's in a position where even standing waves have some amplitude that can then be reduced by the absorber.

So you'd want to make deeper frames for your absorbers so that the Rockwool/Fibreglass is held off the wall. Otherwise you can absorb other frequencies but do very little about the main problems of standing waves.
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Re: Thoughts on these DIY bass traps?

Postby Hugh Robjohns » Fri Feb 24, 2017 4:23 pm

The design of these in the video is quite similar to the Real Traps broad-band absorper designs. The foil helps to extend the absorption down to a lower frequency than might otherwise be the case, but I think calling them a 'bass trap' is stretching the point to some extent!

Nevertheless, much better than nothing... ;-)

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Re: Thoughts on these DIY bass traps?

Postby Urumiko » Fri Feb 24, 2017 4:50 pm

Wonks wrote:You really don't want a relatively hard, solid reflective foil in the middle for broadband absorbers.

Ok, So i read this article http://www.soundonsound.com/techniques/room-improvement and listened to your comments.

I'm just trying to get an idea at this point and will sketchup the final design before buying.

But how does this sound?

This stuff as the bass material for both broadband and bass traps?
http://www.wickes.co.uk/Rockwool-Sound-Insulation-Slab-100mm/p/148842

For broadband try and acheive something like this?
Image

I think id be inclined to make my own frames and wrap them in something like printed Duvet covers to give them a unique asthetic vibe.

Same rockwoool as thick as i can get it in this configuration for bass traps:
Image

Am i on the right track yet? lol
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Re: Thoughts on these DIY bass traps?

Postby Urumiko » Fri Feb 24, 2017 5:00 pm

Hugh Robjohns wrote:The design of these in the video is quite similar to the Real Traps broad-band absorper designs. The foil helps to extend the absorption down to a lower frequency than might otherwise be the case, but I think calling them a 'bass trap' is stretching the point to some extent!

Nevertheless, much better than nothing... ;-)

H

Thanks hugh, I was going to say your response is a bit more in line with what i expected after reading the room for improvement article... then i realised you wrote it haha.

I've took the point that the rockwool is better for decent corner bass traps.

Would you see it worth the hastle of trying to mount floppy rockwool on the wall vs the more rigid foil backed boards? or have is misinterprited the floppyness of the rockwool. lol

My aim is just go get a more nutral space to get basic recording and mixes together in a fairly "transportable" format. and get some usable close micd guitar amps, and vocals without there being extreme room issues. I'd pay a pro to mix my stuff in a propper studio if i was thinking of releasing an EP or something.
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Re: Thoughts on these DIY bass traps?

Postby awjoe » Fri Feb 24, 2017 7:32 pm

I took a similar approach to Glen, but without the metal frames. Two pieces of dense fiberglass together, like he did. But I wrapped them in plastic, and then sewed up some fabric covers to make them pretty. Wrapped in plastic, they slide easily into the covers. (I don't think the plastic's very reflective - the room's really pretty dead with this stuff up - but I'd consider removing the plastic for a better result if I thought it made any difference.) I attach them to the walls using a combination of sashes, bamboo and a sort of monkey hook like Glen uses. I'll post a picture if you're interested.
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Re: Thoughts on these DIY bass traps?

Postby jaminem » Fri Feb 24, 2017 10:40 pm

Urumiko wrote:
Would you see it worth the hastle of trying to mount floppy rockwool on the wall vs the more rigid foil backed boards? or have is misinterprited the floppyness of the rockwool. lol

.

If your rockwool is floppy, then its not the right stuff- you really want RW5 for it to be effective at the bass end, which is not floppy, due to its density
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Re: Thoughts on these DIY bass traps?

Postby jaminem » Fri Feb 24, 2017 10:48 pm

That stuff you have listed above from wickes is not dense enough to control the bass sufficiently. You need this:

http://www.insulationexpress.co.uk/Mult ... -Slabs.htm

If you want to know why look at the table at the bottom left of the following pdf -page 3

http://www.insulationexpress.co.uk/docu ... asheet.pdf

You will note the higher values for absorption of 125 + 250 on the 75mm rw5 - 100mm is even better.

Trust me, I got some rw45 first for my ceiling cloud, good for midst and tops, pants for bottom end. I changed it....
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Re: Thoughts on these DIY bass traps?

Postby Urumiko » Fri Feb 24, 2017 10:50 pm

awjoe wrote: I'll post a picture if you're interested.

Ah cool.. I think i see where you are going with the bamboo, nice idea.
I get what you mean but it'd be cool to see none the less =)
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Re: Thoughts on these DIY bass traps?

Postby Urumiko » Fri Feb 24, 2017 11:01 pm

jaminem wrote:You need this

Thanks that's really really helpful.

I found this video helped me better understand the table also =)

https://www.youtube.com/watch?v=ysdfoA-t1aA
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Re: Thoughts on these DIY bass traps?

Postby jaminem » Sat Feb 25, 2017 8:47 am

Yep, that's right.
So what you're trying to get is an even response through the room, so getting the right rockwool is imperative, as you need to control the bass end as well as the mids, loads of rw45 (the wickes stuff) will dry up the mids, but won't absorb much bass leaving you with an uneven response where you get loads of bass in some parts of the room and none in others, and then next to no mids as all your absorption is damping this range, which can leave the room sounding dull and unnatural.

In practice 100mm rw5 with a gap behind it in the corners and maybe at some points on the walls is going to sort you out - as Hugh has stated anything is better than nothing, but since you're starting from scratch you may as well get the right stuff!

Good luck
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Re: Thoughts on these DIY bass traps?

Postby awjoe » Sun Feb 26, 2017 1:46 am

Image

Where the wall joins the ceiling, I've angled 4" of fiberglass. There's a bamboo pole running along the top and bottom of the two pieces of wrapped fiberglass, and I've bound everything together using fabric sashes. The hooks that support the absorbers are screwed into the studs - they're too heavy to be supported by just the drywall.

You can also see how on the floor, the absorbers are just freestanding in the corners and at the reflection points behind the monitors.

Finally, you can see how I rigged a cloud above the mixing position. They're just resting unattached on the bamboo poles, and I remove them (and some of the freestanding absorbers) when I'm tracking for a more lively sound.

Disclosure: The room's actually a bit too dead when it comes to recording some things, so I record those things in a more lively room with a portable recorder.
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Re: Thoughts on these DIY bass traps?

Postby Urumiko » Tue Feb 28, 2017 4:00 am

I've done a scale Sketch of the room, The aim is to track guitars and still provide a double sofa bed, for guests/other musicians to hang on. As you can see its a bit of a squeese.

I've mocked up What i think may be needed for room treatment. I've used corner bass traps and a load of frames to take Rockwool. Can anyone with experience suggest if I've gone overboard, or am I on the right track?

https://goo.gl/photos/dY5X1x4pqMWXfAku9
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Re: Thoughts on these DIY bass traps?

Postby WebBLAB » Mon Aug 21, 2017 7:52 am

I made this solution for my home production studio, check it out. Maybe it would be helpful or inspirational to made your own design. There are DIY bass traps in corners, few acoustic panels on the walls, ceiling, two stand alone thick panels that works also as bass traps and one big acoustic panel directly attached on the back wall .

http://webblab.sk/3-corner-bass-traps
http://webblab.sk/27-acoustic-panels-si ... d-position
http://webblab.sk/28-stand-alone-acoustic-panels
http://webblab.sk/5-back-wall-acoustic-panel
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Re: Thoughts on these DIY bass traps?

Postby David84 » Wed Jan 08, 2020 9:03 pm

I have thought that using the rock wool covered in the acoustic cloth so the sound particals get through could possibly allow Rock wool particals to get through aswell so it may be better to use a mask while mixing
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Re: Thoughts on these DIY bass traps?

Postby Hugh Robjohns » Wed Jan 08, 2020 11:40 pm

David84 wrote:I have thought that using the rock wool covered in the acoustic cloth so the sound particals get through could possibly allow Rock wool particals to get through aswell so it may be better to use a mask while mixing

Reviving a three year old post with that has to be a windup... But for the avoidance of doubt 8-) or concern in anyone who finds this thread in a search, there are no 'sound particals'! We are concerned with the movement of air molecules caused by sonic air pressure changes through the mineral wool labyrinth, converting the kinetic energy into heat energy.

The holes in the covering fabric are large enough to let air pass through, but far too small to let any mineral wool fibres out.

So there is absolutely no need to wear a mask while mixing... Unless you have a communicable disease or really bad halitosis... :?

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Re: Thoughts on these DIY bass traps?

Postby DanDan » Tue Feb 04, 2020 7:55 pm

A perpetual concern. Like 'will my CR be too dead' All CRs are dead, live with it! https://www.gearslutz.com/board/bass-tr ... eview.html
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