The least expensive is REW,
Originally Posted by StanGeek
Thanks. I've never used those programs. Do you have names of suggested one?
a freeware program but you need to purchase microphone, sound meter, cables and any interface (Phantom Power Supply) card necessary to interact with your computer.
The least complicated but much more user friendly version is the "OmniMic" program which can be obtained here.
Overall, a bit more expensive but much more efficient in time usage; ease of getting up and running.
I can't rightly say which is better as both do an excellent job of providing room measurements so one can on screen, visualize what's what with their subwoofer related room acoustics.
The difference having a room analyzing program up and running is priceless when it comes to fixing those nasty, bass stealing nulls. In the last few days of playing with subs and room analyzing program, I've successfully corrected to two serious null issues (15-17dB each), one at ~28Hz and a, non-harmonic (no sympathetic response) related one at ~88Hz. I still have more to do but what's transpired over the last few days qualifies as an excellent start and could not have been done without the aid of the room analyzing program.
The realtime room analyzer (RTA) also shows I have several, non-speaker related, standing wave issues in the sub-250Hz frequency range. One of them, I'm guessing, is harmonic related; 60Hz vs 120Hz. All of which can't be seen without aid of a room analyzer.
Disclosure: On top of the room analyzing efforts, in an adjunct fashion, DSPeaker's Anti-Mode was added. The Anti-Mode can be considered polish to one's room analyzing efforts.