Sorry to take so long to post this. After eight futile hours of trying to post, I finally realized that my account had gotten blown away. So now I've rebuilt it, hopefully this post will be accepted...
I said I would dig out the SPL meter.
I ran the Avia disc against my rig last night. First I adjusted the master volume so that the left main calibrated at 75db when the reciever's channel adjustment level for that channel was at zero. Then I balanced the other channels' individual adjustment levels plus or minus until all channels were delivering the test tone at 75db.
Finally I switched to the Left Main & Subwoofer test tone. Drum roll, please... Ta Da! The high tone from my left main was delivered at 85db. Avia comes through again: If you match your subwoofer's low tone to that high tone, it will be 10db louder than the other speakers were calibrated to. Always assuming you can keep that low test tone away from your mains, of course. :)
