I have one of the newer Marantz AVR's with Audyssey multi-Eq and I have to concur with Alan on his assessment of this set-up method. At best, it his somewhat hit and miss and in being able to compare the differences on and off, to my ears in my environment anyway, the difference is negligible. Among the drawbacks that I have noticed in pretty well ALL these EQ systems is that with the final result, sometimes crossover settings are not the optimum and bass response is cutback way too much. I ended up doing a manual calibration.

It is also interesting to note in a recent interview with one of the heads of Marantz, with their newer AVR's(including mine), it was made quite clear that they made the philosophical decision to make Audyssey multi-eq calibration "unavailable" when playing back ALL the lossless audio tracks on Blu-Ray. In this particular case, they wanted the sound coming out of the AVR as pure as possible. Interesting.