I have an older Sony receiver and I am in the process of balancing the levels of my JBL Sat10 speakers. I don't have the remote for the receiver so I can't level each speaker individually but on the receiver itself. However, on the receiver itself, even though I can't access a menu to balance each individual speaker, I can access a menu that allows me to balance the center speaker, the front left and right speakers together (just says "front") and the rear left and right speakers together (says "rear"). I had planned on just measuring the sound out of the front left and right speakers and then matching all other speakers to that level but with the rear speakers, using an SPL meter, each rear speaker has a different reading. The left rear has a lower reading and that is because I sit much closer to the right rear speaker.
Basically, since I can only adjust the level of the rear speakers as a pair, can I still adjust the level of each individual speaker by changing the rear L/R balance. For example, I would change the balance more to the left rear speaker until I the dB reading was the same as the right rear speaker. Would this work or would this mess with the overall surround sound.