After my initial enthusiasm with my new 990 and Odyssey Stratos Plus amp, I finally decided to calibrate the front two channels and sub to THX reference levels (I'm only running a 2.1 mostly music setup now). I wonder if I did so correctly.

Since this is a 2.1 setup, I didn't think the 990 could set the levels automatically well and I chose to set them manually.

I have a test CD with pink noise at -15db from peak as well as various test tones at -15 dB from peak: 40 Hz, 100 Hz, etc. I have another CD with more extensive tones as well, but haven't used it yet to measure the overall room response (it has many sub tones and sub sweeps as well, to pick out room resonances).

At my primary listening/viewing position, using the unbiquitous Radio Shack SPL meter, I obtained a 75 dB average signal from the front mains with the 990 set at -23 dB, and I then dialed in the corner-loaded sub on a 40 Hz tone to also produce a 75 dB reading. Figuring, these tones are 15 dB down from peak, I'd get 90 dB peaks with the 990 at -23 dB and thus 105 dB THX reference level peaks with the 990 at -8 dB. So, I set the Left, Right, and sub channels -8 dB down. Remeasuring at 0dB (with hearing protection) verified that I was close to THX reference levels (well, the sub wouldn't hit a 115 dB peak 14 feet away at 20 Hz, but I expected as much: I'd need 127 dB one meter from the sub. I can hit 130 dB at one metre with it not bottoming out, but not at 20 Hz -- at 32 Hz. This is within it's design parameters.

So, have I overlooked anything?

Oh, and yes, THX reference level is VERY LOUD!. At most, I watch/listen 12 to 16 dB down from it.