Why does Denon 3910 default to PCM for sacds?


I have been made aware of this by Alex Peychev. He states, "Anyway, the 3910 Source Direct ON/OFF mode is in the On-Screen menu in the Audio Settings. You need a monitor. When you select Source Direct ON you have true DSD. If it's OFF the DSD is converted to 176.4/24 PCM. Be aware that the Factory Default is Source Direct OFF, so the machine converts DSD to PCM. You need to go and change that." I have tried it both ways and it makes a substantial difference in the realism of the sound.

I suspect that Denon's indifference to sacd and the desire to hear sacds in dsd conversion is overridden by their expectation that most will be interested in only dvds and HT.
tbg
What is the optimal setting on the denon to achieve the best 2 channel sound for redbook CD's?. I am using the Denon 2800 MKII as both DVD and CD transport (which by the way is connected on BEl Canto Dac). The 2 digital setting options are 1- LPCM Select:either ON or OFF, and option 2-DIGITAL OUT: Normal, PCM or OFF. For DVDs option 2 must be set to PCM orthe audio will simply not work, but for CD's(under option 2), I found there to be a audible difference in sound when set to "normal" as apposed to PCM. My personal preference for CD's isoption 2 - Normal, but what about option 1? should PCM be set ON or OFF?
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Tvad, I think that setting Source Direct ON you have true DSD for sacds and pcm for everything else, but I think this may have implications to MCh bass management. I don't think it affects how stereo cds, hdcds, dads, or dvdas sound.

Rudd, I at least know nothing about using the Denon as a transport. I would assume that the digital out can only be PCM and probably only 44 MHz.
To add to what Rex said. How many HTs have 5 full range speakers that are equidistant from the listening position? Defaulting "source direct" to "off" makes a lot of sense.
Again for those using the Denon 3910 as a stereo source, I can now confidently state that when you make the change of Source Direct to ON means that you have to wait again for break-in. I guess this is the dsd dac. After better than a week in the new setting, I am now just overwhelmed by the need to make this change. Never have I had sound like I have now. I should also say that your results may vary if you are not using the Exemplar 3910.