Digital Coax Output - DSD is always converted to PCM

ROSE Products RS250
#1

Hello. I am enjoying my new RS250. I have it hooked up using the digital coax output to a new Anthem AVM90. I notice that when I try to play DSD64 (2.8Mhz) it is always converted to PCM 88 and when I play DSD128 (5.6Mhz) it is always converted to PCM 176. I am not sure why this converts when I use DSD Native. I know the processor sees DSD as I have an Oppo203 and its output is bitstream and DSD labeling comes right up on the AVM90. Is there a reason that the RS250 cannot output a true DSD file through its digital coax connection? I am assuming that through the USB output it would…does the optical output provide true DSD output?

I have also tried all (3) choices for DSD output with no difference at all.

Thanks for your time and insight.

#2

Hello @BubbaK

Coax output only supports up to 192KHz. So DSD is converted to PCM format.
What are the output settings of Anthem AVM90? It seems don’t have “USB IN”
I recommend you to use Analog In to play DSD file.

Thank you

#3

Thank you. Is there a reason why the digital coax cannot output true DSD file? Is it a hardware limitation or software limitation? I am just curious about this.

Thanks again for the help.

1 Like
#4

Hello @BubbaK

When playing DSD files with coaxial and optical output, PCM 192kHz is the maximum output.

Thank you

#5

Dsd can only be used for direct 1:1 out. You cannot manipulate a digital DSD stream.

That means if you have selected ‘software volume on’ it converts the dsd stream to PCM to be able to calculate the bit levels for your desired volume.

If you disable ‘software volume’ it will send the 1:1 dsd out. This means you have to use your (pre) amplifier to turn down the volume when it’s passed the DAC as ANALOG.

DSD was originally intended by Sony and Philips only for storage of masters in the best quality. Not for mixing.

I noticed the same and fixed it.

It is a strange but safe choice by the Rose engineers that if you select software volume it disables DSD-direct instead of the other way around. Normally if you select DSD-direct your output goes full blast. Volume is best done on the amplifier.

#6

I have the new rs130 streamer connected to my Yamaha CD-S2100 sacd via coaxial……should I use NativeDSD , dop , pcm ….or something else ?...this is all new to me and I don’t fully understand it all…I’m just trying to get the best sound….

#7

The output from a SACD player is complicated. Due to copyright concerns you can’t get DSD out of any player. You can only play the DSD layer of the SACD if you use the internal dac (ESS ES9016 which is kind of old). The digital output will only put out PCM.

Normally, from a digital player or streamer, if you play a DSD file (DSF, DST or an iso) you can choose to output native DSD over usb. DoP means DSD over PCM, a DSD stream wrapped as PCM (in my experience DoP doesn’t sound as good as pure DSD). Or simply converted to PCM. But iirc you don’t have all those options from any SACD player (except the Playstation and some old Oppo mediaplayer which aren’t strict SACD players).

So for the best soundquality you will have to trust your ears: do you use the pure DSD from the analog output of your SACD player produced by the older dac-chip or do you prefer what an external DAC (or the Rose) make of the PCM output?

The problem of DSD is that it is master quality and big media companies like Sony don’t want to share their invaluable masters catalogue without copyright protection.