Nick:
This disc is almost certainly compressed out the wazoo, with levels nearly always at 0dB FS. That said, here's a little chart to break down what 0dB FS is for various volumes vs what you're seeing on the meter. Note that Ref(1) is 1 speaker Ref(2) is two speakers. This further assumes when you calibrated, it was to 75dB SPL, c-weighted:

Code
Vol....Ref(1)...Ref(2)...Actual

75.....93.......96.......94
80.....98......101.......99
85....103......106......105
90....106......109......109
So in this case, theory and practice are lining up pretty nicely, and well within the bounds of your SPL meters acccuracy smile

Regards,

Surround Music Fan/Computer Geek/Curmudgeon in training.
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