Acoustic Treatment - DIY Diffuser and Bass Trap

Hi.. I am thinking to DIY diffuser & Bass Trap. What's the best acoustic treatment for my room size 9' (W) x 11'(L) x 9' (H) ? ( Timber Flr & Plaster Ceiling ) Currently using egg racks as a diffuser for 4 walls. Because I have a cube room ( worst for acoustic ! ). Some says. the best for cube room is to install absorption panel for all the walls. True ?

or

diffuser panel for the front and both sides. Absoption panel for the rear ( behind our ears )

please help..

Welcome anyone to post their DIY Diffuser & Bass Trap pic.

@tubejunkie

This had been discussed at the following thread:-

https://www.hifi4sale.net/equipment-discussions-f6/absorbers-and-diffusors-t865.htm

Maybe you can get the information you required there.

tycham wrote:@tubejunkie

This had been discussed at the following thread:-

https://www.hifi4sale.net/equipment-discussions-f6/absorbers-and-diffusors-t865.htm

Maybe you can get the information you required there.

oh..good. thx..Cham.. will check it out now..:p

Hi,
For me I think the basic principle is not to let the reflections/echo interfere too much with the direct sound from the speakers to your ears but at the same time you should not eliminate completely all reflections as it will sound 'dead' and not lively.

I follow this simple logic (cover between 1/3 to half the area of wall is normall sufficient):-
1) Front wall (behind speakers) should be partially reflective so we put DIFFUSERS, especially directly behind and between speakers.
2) Side walls (L&R) - use mirror to 'locate' first reflection points of both L & R speakers and use ABSORBERS, leave other areas free at first (maybe add some DIFFUSERs later)
3) Rear wall (behind listener) - use ABSORBERS as we dont want the sound moving past us to 'return'. For me, its the whole wall.
4) Floor - cant do much since we need to walk on it! So just put CARPET which is actually a partial ABSORBER
5) Last but not least - Ceiling which many people ignored but greatly affect the sound - put DIFFUSERs - probably one third the area of the ceiling around the middle portion
With the basic treatment in place, it should sound like a bigger room and image better and you go for fine tuning like speaker placement and further treatment. Please bear in mind that most ABSORBERs and DIFFUSERS are efficient in high freq and mid freq only and are not effective in low freq. Low freq absorbers (bass traps) are bulky and special function, there is no short cut. So, finally, the bass part which is difficult part and need trial and error work but placing bass traps at corners is a starting point. Just my 2 sens opinion. Thanks for reading.

Much that has been said by CLH is valid. Just to add a couple of points.

Personally I prefer a more lively room and would avoid too much absorption. 2'x4' panels on both side walls would be sufficient. In contrast with CLH's opinion on putting absorbers for the whole rear wall, I prefer all diffusion. I would recommend that you start at the front and side walls first for starters, especially the side walls since I presume the speakers will be very near to the side walls in your smallish 9'x11' room. Place diffusors just right beside your speakers on each side extending up to the front wall if possible. Sorry to disappoint but your egg racks currently used as diffusors will not cut it. You are better off using shallow open bookcases. The cheapest commercial diffusor you can get in the market is the Skyline type diffusors sold by Hiway Laser. If you went to the KLIAV show in July you would notice how these diffusors look like and how they place them in one of their demo room. You need to get minimum 8 pieces of 2'x2' in order to perceive an appreciable sonic difference. Personally I like the wood diffusors better but they cost considerably more. Your timber floor is ideal -all you need to do is to just get a small piece of rug and place it in front of the speakers, that's it. As for plaster ceiling, I wouldn't mess with it unless you are really in the advanced stage as mounting anything on top of the ceiling requires careful planning and can get messy -mounting brackets would probably need to go through the plaster ceiling and hook onto the rafter support above.

Unfortunately most professional room treatment products are not easily available in Malaysia as most good ones are very costly. Some of these panels can do both absorption and diffusion as the absorption panel has built-in strips that partially diffuse the sound waves. For DIY bass traps you can refer to member Auronthas for tips since he has made some himself. Just need to practice a little caution when handling the rock wool material.

Have fun.

CLH had done well in covering almost all the aspects of room treatment.

This are excellent stuff to treat delinquent low frequencies.



Those in the photo are of 40kg/cu. m density. Maybe can make a 1200x600x300 wooden box to house it(all 6 pieces in a bale), with the front using perforated panel covered with speaker cloth.The higher the density, the better the absorption.

I have the 80kg/ cu. m one but then I am just too lazy to lug them home to try.

As for treating the ceiling I guess, since treatment would often affect the lights and the fact that it would be more of a hassle, most people would leave that out. Especially so, if anti-focusing surfaces are required.

I find that the easiest to handle, most effective, and probably cheaper as well, wall absorption panels , are the acoustic ceiling tiles. Can just frame them up using timber frames.

Have all the data too.

cool ! thx a lot guys.. finally have some idea how to set up my room..
I am going to DIY a 2'x4' x 3" timber diffuser by using solid Meranti strips size: 2 6/8" x 3/8" for internal divider. And also 2'x4' x 2" bass trap wth rock wool. hehe.. hope can get some good result

tubejunkie wrote:cool ! thx a lot guys.. finally have some idea how to set up my room..
I am going to DIY a 2'x4' x 3" timber diffuser by using solid Meranti strips size: 2 6/8" x 3/8" for internal divider. And also 2'x4' x 2" bass trap wth rock wool. hehe.. hope can get some good result

You'll never know until you had tried. Enjoy yourself.

This would be worthwhile reading.

http://www.harbeth.co.uk/usergroup/showthread.php?p=5833#poststop

Will a well treated room, ie. providing a really flat room response sound
really really good? Assuming the room has being measured after the
room treatments are done! Anyone here got such a room I can go listen
too?


btw how will such a treated room help the unkers enjoy their music? In case you don't know, older unkers are more affected by reverberation times than the much younger audiophiles!