I will admit I was unable to demo the unit, but have previously had other marantz so was happy to take the risk, To my ears the 2ch audio is excellent, I will point out however that I do have 2 Marantz MA6100 monoblock, amps (Bi-Amplified with receiver) helping to drive my speakers.
A few years back I Did a weekend home demo on my system with the 5003 and Monoblocks against a Rocsan Candy Amp, i was more than happy with my system, I also recently did a demo against a Yamaha Preamp driving my Mono's v My 6003 doing the same, again happy to stick with an AV amp as my main source. Another Hi Fi Magazine in April Reviewed it against a Yamaha RXV1900, NAD T755 and Onkyo TX-SR875, For an audio amp (Music) perspective It came out on top by an easily perceivable margin and said it compared well against integrated amps.
I do not have the kit space to have seprtate Stereo and AV setup, but I think I have an excellent sounding AV syatem for music replay.
With respect to Audessey I don't use it with music, Pure Direct for me this switches off everything not related to the audio being played, and i don't have a Blue-ray player so cant tell for sure if it would be an issue, It will definatley decode DD/DTS from DVD and do Audessy but to be honest For Surround I did the audessey setup, then transferred those settings in to the personal EQ set, I felt is was Bass light and wanted to tweak the settings.
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