One popular way one can tune their system is by watching the frequency levels on the RTA while tweaking the frequencies with an equalizer. Access to an RTA, however, can be difficult and expensive.
If you are content with a rough tune to get rid of the major resonances and peaks, and cannot afford an RTA, you can purchase a Radio Shack sound pressure level meter (dB meter) for $40.00 (digital).
The Radio Shack meter is fairly consistent (standard deviation is about 0.5-1.0dB) and accurate - especially when measuring the midrange. It maxes out at 125dB. Various corrections are available on the internet in order to improve accuracy. When measuring using "slow" response and "C" weighting, the following corrections seem to be most accurate:
After purchasing the SPL meter , you would then make a test tone CD filled with test tones of various frequencies at a 1/3 octave step. You can then measure the dB of various frequencies and either boost or cut the frequency with an equalizer. You can download the MadPSI test tone CD by right clicking and "save target as..." this link
. The file is compressed by WinRar, and each sound file is in mp3 format (high quality variable bit rate). The compressed file should have the following mp3 files: