Since adding the 7500, marantz and larger and more efficient Klipsch towers, I have an Audyssey issue.

Towers are set at -9.5db upon completion, and center is bottomed out at -12db. Luckily, the center is matching well with the fronts SPL wise after talking with Audyssey, but the larger Klipsch center I intend on getting may be an issue.

A 6db inline attenuator was suggested, between the Marantz and 7500 for the center (may do all 3), but I am wondering if the gain difference in the XLR channel would be a better move (use balanced instead of unbalanced). Or would that do nothing/make things worse?

Thanks.

I think it would make it worse by about 6 db since the XLR gives about that much MORE gain than the RCA connection. Try using a handheld meter to verify the reference level.

Thanks, that is what I was thinking and have been reading.

I did verify with my meter, the mains are right around 75db, and the center is 1/2 to 1 db higher. I am going to add a nice 6db attenuator to the center RCA to bring this in line.