I use the BDP-83 for Bluray and CDs. I have it connected via 5 analog channels and HDMI. As I understand it, Audyssey applies its magic to the analog outputs just as it does in HDMI mode otherwise it would sound completely different than the HDMI mode. I don't find a big difference between the two but I don't have SACDs or DVD-As. I can't see anything in the manuals that say Audyssey is not applied.
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Music system
Model 990/7500/Magnepan 1.6 QRs/Technics SL1200 MK2/Aperion S-12 Subwoofer/OWA3/Sony NS75H DVD
APC H15 Power Conditioner

TV System
Large Advent Loudspeakers/ Polk center/Monoprice surrounds/Panasonic Viera 42 inch/Onkyo HT-RC260/Sony BDP S590/Directv


Home Theater System
Onkyo PR-SC886/Outlaw 7125 Klipsch RF-82 L/R,RC-62 center, RB-35 SR/SL, BENQ HT1075, Outlaw LFM1-EX/OPPO BDP-83/Directv
Harmony ONE
Blue Jeans and Monoprice interconnects
APC H15 Power Conditioner