Personally, I don't think an SPL meter is nearly as necessary in a 2-channel system, though it CAN help you to balance a subs' level and chart bass response!

WARNING: This might cause you to hate your room! If you are happy with the current sound of your system, walk away! Your mileage might vary. Ask your Doctor. Erections lasting longer than four hours...........

::::::: No disrespect to Axiom, but my favorite woofer is my yellow lab :::::::