How to diagnose the need for room treatment?

Although I don't have the room optimization experience that most of the others have had, I'd like to offer one small but I think significant point.

Particularly once you get above bass frequencies, tuning the room for flat frequency response using a test cd, microphone, etc., is not necessarily going to get you the best sound, and in fact probably won't. The microphone is not going to discriminate very well, if at all, between early arrival sound (the direct path from the speakers to the listening position) and later arriving sound (reflected off of walls, ceiling, etc). But your ears will!

I believe that some of the more sophisticated (and expensive) equipment that does this sort of thing can help to take arrival time into account, in a meaningful manner, but a Radio Shack sound level meter used with test tones from a cd will not. Although I think you will get meaningful results that way in the deep bass region, because of the long period and wavelength of the tones, and the consequent lack of timing sensitivity and directionality of our hearing at low frequencies.

Regards,
-- Al

Recommended reading for setting up your system for better sound: "Get Better Sound" by Jim Smith. Smith is a professional sound consultant whose setups have won several "best of the show" awards. His book walks the reader through a systematic method of getter better sound from your system including room treatments, if needed. The book has received several raves on boards and ezines. I found it very helpful.

Guys,

Thank you very much. Really. I have a fair amount of reading ahead of me + getting acquainted with test CDs & SPL meters. I'm not looking for quick fixes, so getting a good understanding of how my room/system behave together and how to improve the sound sounds like fun.

I hope you don't mind me asking back again for further guidance in a while. Will check out the room accoustics forum too.

A lot of good info/advice. Thank you!
Horacio

Al said, "I believe that some of the MORE SOPHISTICATED ( AND EXPENSIVE) equipment that does this sort of thing can help to take arrival time into account, in a meaningful manner,"

I take exception to those statements. The REW (Room EQ Wizard available at the Home Theater Shack) is sophisticated and does time domains. It is for FREE FREE FREE FREE FREE

Bob

Al wrote: "Particularly once you get above bass frequencies, tuning the room for flat frequency response using a test cd, microphone, etc., is not necessarily going to get you the best sound, and in fact probably won't. The microphone is not going to discriminate very well, if at all, between early arrival sound (the direct path from the speakers to the listening position) and later arriving sound (reflected off of walls, ceiling, etc). But your ears will!"

I think your comments apply better to the bass frequencies, not above bass frequencies. In the bass, the arrival/decay times are more easily measured and corrected whereas at higher frequencies room mode interactions approach randomness. Thus, at those higher frequencies, only FR adjustments are feasible.

Kal