Room Treaments - Where To Begin...

I'm constantly amazed that audiophiles can go on at length about VTA, upsampling, damping factor etc. but when it comes to the most important component, the room, they have little or no understanding. This is forgivable to an extent. Without having heard the enormous improvement attention to acoustics brings to the party it is difficult to conceptualise the transformative result.

All rooms need treatment, without exception. Even the Royal Albert Hall required  some monster upside down 'mushrooms' to kill excessive echo.

The second post you received from member @dill provided you with lots of good info and there is tons more. Obtaining your advice from those links is preferable to getting conflicting opinions from ill informed posters here on the 'gon.

Once you have gained some understanding, which you should relish with glee because this is the only way you will ever get to hear your system truly perform, you will soon realise that guesswork does not enter into the requirements of treatment.

You will understand about wavelengths , how to calculate and how to deal with them. You will also learn that a rug, drapes or wall hangings do very little because they only provide narrow-band absorption. Now I expect someone to counter with 'I just placed a rug between the speakers and it made a huge difference" Well yes of course there will be a small improvement and the comment simply comes from them never having heard what a carefully sorted room sounds like.

The biggest thing happens down low in the Schroeder frequency range where bass energy combines, sometimes creating peaks and sometimes nulls. Bear in mind that a full null means zero sound. I repeat, when there is a null there is no sound, zilch, nada. It's MIA and no, no DSP or equalisation can bring it back. Even a partial null, say 15dB below average, could not be corrected because your amp is not powerful enough and the speaker voice coil would instantly fry.

Above the Schroeder frequency, average about 250Hz you have a reverberant field which can be addressed with diffusers and absorbers. This is important: the smaller the room, the more absorption is needed. The bigger the room, the more diffusion is needed. In practice the average size living room need both.

My direct advice after reading the material @dill provided is to read even more and then buy a suitable mic. for less than $100 and download a free program like REW and get started. Even if you get the professionals in you will at least be able to measure the before and after results and so avoid the possibility of being oversupplied which has happened to a friend of mine when he left it all up to GIK.

Imagine now hearing all the missing details in the bass and the fact that unless you act appropriately things will not change. If you want to go all the way then look into a multi-sub addition which will smooth out the lows even more. Can this bass problem be sorted with multi subs only?  Well yes the extra subs will smooth the room nodes but you still have the issue of overly long decay across the full spectrum.  Looking at this another way:  installing multi-subs will smooth out the bass nodes and the addition of bass traps will reduce the long decay. Win win. Your ability to measure T60 yourself will get you to head of the class.

Have fun.

Yes, Ethan Winer is a good call. His YouTube videos are interesting and informative. 

I forgot to mention, there is also the forum 'gearspace' formerly known as gearslutz, which has a whole section on acoustics with articles on building stuff yourself and on measuring, which is easier than you think even though I don't know what you think, I think. There is a much larger community of experienced guys and well worth a visit.

Hi rixthetrick,

Difficult to apportion a budget as a percentage of total value of your system. I think of it as a case of taking X amount of $ to tame the room's acoustics which then will provide the correct acoustical environment to allow any and all systems to be heard at their optimum level of performance.

The room proportions do make a difference but are seldom found in the real world. The golden ratio or Fibonacci Sequence help with spreading the room modes so you do not get massive build up of certain frequencies. This is seldom found and is not an insurmountable problem. If possible avoid any one dimension being exactly twice or half that of another. So a cube would be absolutely worst case.

Any room, however, can be made to sound good. I made all my bass traps, diffusers and absorbers myself which does not cost that much. I used to visit demolishers and buy the insulation panels for peanuts. Look for Owens Corning 703 or similar.

Start with bass traps which need to be rather large but the divorce is worth it for good sound.  😎   These need to be big, you're dealing with long wavelengths so those dinky little scraps of foam Amazon sells are useless. Google superchunk DIY bass traps for an idea.

Corners are the place for BTs, any corners, the more the better. Usually the 2 front vertical corners are used for floor to ceiling traps but instating them horizontally along 1 or 2 wall/ceiling corners work just as well. This alone will make a very large improvement.

Place absorbers at the first reflection points. As I mentioned curtains, drapes or skimpy wall hangings do not absorb over a wide range of frequencies. Build or buy frames at least 4" deep to act as broad-band absorbers. The OC703 is available in panels 2'x4' so use frames to size or multiples. Panels 4'x6' or 3 panels 4'x2' with a small space between look smart and can be covered in different colour fabric.

A 'cloud' attached to the ceiling is a great way of eliminating the troublesome floor/ceiling bounce and does away for the need of a carpet or rug, though a rug will not harm anything. i helped a mate with a ceiling cloud and fitted an LED strip light around the perimeter on top. With the remote that came with it looked very neat, could change colour and dim to suite.

I am selling the old stone cottage and have abandoned any further work on the acoustics. I use Omnimic to measure which shows a consistently good T60 but also shows a slightly lumpy bass. Based on before, during and after screens that I need one more BT and job done.

Persevere with what you have started. You are clearly DIY capable so go for it and good luck.