Author Topic: Couch used as a bass trap  (Read 3924 times)

Offline MetalMilitia

Couch used as a bass trap
« on: August 30, 2010, 05:23:31 PM »
Hey guys

The wife and I have bought a new place so I am kitting it out with new equipment and new furniture

Now before I install anything permanently I want to treat the room properly (lounge will be used as the theatre). Acoustic panels are being built for the walls at the moment but I'm still going to need bass traps

The problem with most bass traps though is that they are hideous and I don't like the look of circular/triangular tubes in the corners of the room. This had me thinking......I'm buying an L shaped leather couch that will span the length (well almost) of two of the walls

Could I not fill the inside of the couch with Think Pink or rigid fiberglass? The underside would then be stapled closed again with speaker cloth or something with similar properties

Is this a crazy idea or can it work? Theoretically it should

Offline Robert_E

Re: Couch used as a bass trap
« Reply #1 on: August 30, 2010, 05:50:11 PM »
Don't think you need to stuff the couch at all. Just a normal couch converts a lot of sound energy into kinetic energy

Offline Hennie

Re: Couch used as a bass trap
« Reply #2 on: August 30, 2010, 06:00:25 PM »
The couch itself should have a significant damping effect, but if you are planning a listening position in that L-shaped corner couch, think twice. Your bass will be incredibly boomy in the corner. If the corner couch is meant for visitors only and you are planning your optimum listening position elsewhere, I think you are on the right track.

Offline Greyman

Re: Couch used as a bass trap
« Reply #3 on: August 31, 2010, 02:35:39 PM »
A big bulky couch will help contribute a bit to mid and high end absorption in your room.Being leather there will also be a fair amount of reflection apposed to having a fabric couch.. That being said couches do not have the density to really absorb much low end. I would as Hennie said have your optimum listening position elsewhere would be best. Depending on the room size having a reflective object at the back of the room is not the worst thing as long as you have a handy couch throw to cover when you are having a serous listening session.In my very humble opinion there is no escaping proper base trapping for all 12 corners not always the most practical is a home environment but at the very least have the 4 major wall corners taken care of. I would treat the room with bass traps first as bass is always a major issue.. then move on to the first reflection points...and so on untill you get the room as dead..or lively as you prefer...just a thought :)

Offline xrapidx

Re: Couch used as a bass trap
« Reply #4 on: August 31, 2010, 02:41:10 PM »
Without derailing - is there somewhere I can read up on this sort of thing? Considering I'm doing my new room as well - and have no clue as to room treatments.

Offline Greyman

Re: Couch used as a bass trap
« Reply #5 on: August 31, 2010, 02:50:28 PM »

Offline PAPPA3

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Re: Couch used as a bass trap
« Reply #6 on: August 31, 2010, 08:15:39 PM »
Sorry to burst your bubble  :D, but IMHO the couch thing wll work to a certain extent.  However, bass builds up in all the corners where your walls meet, including the ceiling corners.  It also builds up where walls and floors, and walls and ceilings meet.  The best (but no wife approves of this) is to start with treating your room corners.  Improvement will come with placing traps along the wall. 

To decouple subs, a small sub-trap can also be used.  The only thing that really works is high density rigid fibreglass (20cm thick or more, built up by adding the regular 50mm sheets/tubes together).  they are better than pink fibreglass.  they serve as velocity absorbers by slowing down and absorbing the wave.  Forget about thick foam trapping bass.  It may trap/absorb midrange and treble, but not stubborn bass.

Reflection points on wall, floors (and if you can get away with it - ceilings) will help with echoes and room flutter.  These can be treated with 50mm panels.  having curtains, furnishings, carpets, rugs, throws, etc., also help tame mid-high frequencies.  be wary of overtreating the room and killing too much sound.  Room treatment will help your speakers come alive, some consider a 40-50% improvment in sound.

Bass is a major culprit known to rob you of clarity.  Bass treatment actually improves your bass instead of 'absorbing' it.  Bass will be clearer, tighter, with less 'wild resonance' reverberating all over the room before the wave dies.  Without treatment, you could drive yourself crazy turning speakers up and down trying to get a good volume/clarity ratio!

Offline MetalMilitia

Re: Couch used as a bass trap
« Reply #7 on: September 01, 2010, 01:49:21 PM »
Thanks for the input gents

I won't be sitting in the corner of the room, more or less in the centre of the couch, it will be place against the back wall. Won't be able to move the couch away from the wall as this will block the entrance to the patio

@PAPPA3 - do you have a source from whom I can purchase some rigid fiberglass? I would like to use them when building panels for the walls

Bulky bass traps in corners is going to look silly so I will have to go without

Offline PAPPA3

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Re: Couch used as a bass trap
« Reply #8 on: September 01, 2010, 09:00:18 PM »
You can get the rigid fibreglassin sheets or tubes of different dimensions from Egoli Insulation & Sheet Metal Works, Log Square, 28 Maddison St, Jeppestown, Jhb. (011) 614 4141/0972; 0824732849.  If you're planning to glue sheets together, buy 5l of glue from them (no other glue will work as well).  the stuff is very itchy, so take plastic bags, and keep covered when you work with it, or you'll be itching all night long :P

I bought the large tubes, and smaller tubes to go inside.  then I glued/fixed them together.  Then had it covered in 10mm foam at upholsterers to even out the uneven edges.  Then they were upholstered professionally. They look great and work well.  I also built panels for the walls and a subtrap to decouple the sub from the floor (which I've given away when I sold my old sub); plus 2 corner-mounted ceiling bass traps.  Will post pictures when I get a chance.  Call me on (011) 692 4023 and I can explain how I did it.  Worked out to about R700 each for a 1m high tubular bass trap with a diameter of about 450mm, inlcuding all material and to have them professionally covered.  They don't look hideous.  everyone thinks they're a piece of furniture, but the wifey & I know the truth  ;).

Offline MetalMilitia

Re: Couch used as a bass trap
« Reply #9 on: September 01, 2010, 09:32:49 PM »
Nice thanks! Sounds like you been a busy guy regarding room treatment

You mention you had foam added to even the panels out. Is the rigid fiberglass not very even already? (assuming from pics i have seen on the US forums, perhaps they get different types to us)

Have you done any testing or taken readings to see what frequencies were absorbed by these traps
Would really be interested in seeing pics of the completed panels

Offline PAPPA3

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Re: Couch used as a bass trap
« Reply #10 on: September 02, 2010, 10:35:46 AM »
The foam is only needed on the tube bass traps.  When the upholstery is pulled tight, without the 10mm foam, you will only accentuate uneveness.  Remember fibreglass is intended for industrial use, so not great cosmetics there.  Plus the foam acts as insulation for the fibreglass loose fibres which could theoretically pass through the upholstery.  It only adds about R100-150 to the cost & labour, but you won't regret the finished result.  I covered the wall panels with cheap material on the fronts to contain loose fibre, before I put the decorative cover over.

Please believe me when I say the fibres are invisible, and itchy!

I'd need someone who's brainy to come and take readings.  Otherwise I can hear an audible difference.  Just watch sitting close to those back wall.  I have the similar problem re seating position.  Bass travels accross between the side walls.  Just a 60cm move forward makes an incredible difference.