Brian, very interesting article, thanks....it seems to verify what I've found using Fight Club's Optimode tones, i.e., that particular disc is indeed a valid source of calibration tones.
From the article>"Unfortunately, with 'Fight Club' being the only exception, the THX Optimode calibration...
The tones for Optimode (on Fight Club) have been recorded at 75dB, as noted in the Optimode section of that disc....my testing of the tones against those on the Video Essentials disc confirmed their accuracy.
Vin
Johnson, Tan makes a good point about the receiver's test tones being off....I also found this to be the case.
If you have the Fight Club DVD you could use the Optimode section that's included on it to calibrate your speakers....I've tested it against Video Essentials and found it to be accurate.