For testing, a local shop should have an Audio Control meter, obviously your not going to dish out the 2g's for this meter. The radio shack one is ok and you only need it to read low numbers so that you can find your peak without your neighbors killing you. I would ask a local shop for their assistence. Go back to where you got the equipment, if they did the install they should be more than happy to help you out and hopefully havw the audio control mic
Class D amps are good on electrical system and are more efficient, but they produce alot of distortion. You may hear a difference in the sound of you subs, I know I could, the bass was not as crisp and tight (damping factor low I guess) thats just MHO.
Good Luck, let us know how you do. Also if they are using different mics and you score gets lower, dont be discouraged, it happens all the time, as long as both mics read the same then everything is ok. Its when the right lane mic reads louder than the left lane that you complain...LOL
