If I enable DSD in DoP format in Output Format, all file types from my library are converted to DSD format during playback.
Correct. That's what that function does. If you want to re-encode
all output to AC3, for example, you enable that setting in there. The Output Format setting is used for DAC
compatibility. If your DAC
can decode PCM, then you should never enable this function. That's why it says this
in the Wiki:
If selected, all audio output will be re-encoded to this format before being sent to the audio device. This is rarely needed, and is only recommended if your audio device can only play a particular format successfully (such as playing multichannel audio over SPDIF or when using a DAC that only works with DSD formats).
It was primarily useful for sending multichannel audio over SPDIF to an AVR, in the days before HDMI. But, if you really, really, really want it to re-encode
everything to DSD, then that's where you turn it on.
Is it possible to use DSD playback for DSD files only and disable all DSP setting for playback other file types automatically?
Yes. That's called bitstreaming. Bitstreaming bypasses the DSP and MCs entire audio engine. The files are sent directly to the DAC without being decoded. When bitstreaming, MC has no impact on format compatibility and cannot alter the audio in any way (
including altering the volume).
It also doesn't matter what the DSP is set to because the entire DSP can only operate on PCM data passing through MC's audio engine. When bitstreaming, MC never decodes the file, and never routes it through the audio engine, it just copies the data file directly to the audio device driver's output buffers.
So, you can have different settings for native-DSD files and "everything else", by configuring the DSPs (particularly Output Format).
Enabling "bitstreaming DSD" does not play DSD128 or higher with realtime convertation to PCM.
I don't know what you're talking about here, because you mix up two different things. Bitstreaming cannot include realtime conversion to PCM.
If MC has bitstreaming set to DSD, then it does not decode the DSD-native files, and sends them through to the DAC unaltered (and undecoded). This, however, would
only apply to native DSD files. Any other files (PCM files, FLAC, WAV, MP3, etc) don't get bitstreamed, and are processed through MC's audio engine normally (including any activated DSPs). I think you're having trouble because you have the Output Format DSP all messed up.
Follow the Audio Setup Guide, and do what it says:
http://wiki.jriver.com/index.php/Audio_SetupThen, if you want to pass DSD files through to your DAC, enable
only the bitstreaming setting. Note that with some DSD DACs you
must have the system volume locked at 100% for it to work right, so you should disable the system volume control in the OS if possible (some drivers do this for you, or automatically maximize the system volume when DSD playback starts, but others do not).