Rotel and HDCD processing

[madmac]

Hello all,

Most of the time I send an analog signal to my Rotel amp for CD listening because I find the DAC's in my Marantz to produce better audio than the DAC's inside my Rotel. However, when I want to listen to HDCD's I need my Rotel to do the conversion and send a digital signal to the amp using a digital coax cable from the CD player.

Interestingly, my Rotel goes into 2ch stereo (It's set to 5ch stereo by default) when fed a HDCD digital signal and it indicates HDCD on the front display. However, I like to listen to my music in 5 channel stereo most of the time and when I switch to that format, the HDCD display goes away! Am I to assume that the HDCD audio is now gone and it's playing the regular CD audio??

I'm 90% sure this is the case because the 5 channel stereo mode requires a different kind of digital processing??? Am I wrong here ?

[Ovation]

If you use the digital output of your CD player, it means the Rotel DAC is doing the work. If you use the analogue output of the CD player, the Marantz DAC is doing the work (assuming a Pure Audio or similar setting on the Rotel). If the analogue output of the Marantz is processed by the Rotel in any way (Dolby PLII Music, 5/7 channel stereo/etc.), then multiple DAC/ADC/DAC conversions, involving each unit, are occurring.

I suspect the HDCD decoding is limited to 2 channel and any use of MCH processing is turning it off--OR the display is simply not equipped to show both HDCD AND whatever processing is going on. In any event, whatever benefit HDCD provides is overwritten by further processing, so it matters not at all for MCH processed sound. HDCD is only equipped to offer a difference in 2 channel playback. And the Marantz DAC in your system is only influencing the sound quality if you run the Rotel in some type of Pure Audio, entirely unprocessed setting. Otherwise, the Rotel ADC/DAC are, together, eliminating any contribution from the Marantz DAC.