[HansSo]

Ever since I have my Stream-9 I have had some questions about SRC on the DAC-9.

The documentation for the Stream is clear about SRC, what it does and when it does it. The documentation for the DAC-9 just mentions that the DAC-9 contains a SRC IC but gives no further information.

Does SRC in the DAC-9 take whatever samplerate I send to it and converts that to some fixed samplerate before sending the data to the DAC chip (AKM4490)?
What is that samplerate? (the datasheet for the AKM4490 states that the maximum samplerate it can handle is 768kHz)
Is there any difference between sending PCM or DSD to the DAC-9?

[Jargier]

Hi. A bit late, I rarely visit the forum.
I was wondering about this myself.
In my case, Foobar2000 (Win10) (Nuprime drivers) supports only 384 kHz DSD. I can't hear the difference between PCM and DSD. It does not support DSD512 or even DSD256 natively. I do not know why. I have a detailed system.
I'll have to check it out on my Macbook - Audirvana and Colibri.

[rustydoglim]

Regarding sample rate conversion, there are proprietary details in the SRC and DAC chips that we are not familiar with.

The DSD and PCM issues are mainly software-related.
This answer came from NuprimeAI (CustomGPT):

To play DSD (Direct Stream Digital) format music on a DAC (Digital-to-Analog Converter) device, there are several methods available:
1. Native DSD Playback: This is the most direct method where the DAC supports DSD files natively. The DSD signal is sent directly to the DAC without any conversion, and the DAC decodes the DSD stream to analog audio.
2. DSD over PCM (DoP): For DACs that do not support native DSD playback, DoP can be used. DoP is a method to send DSD audio through a PCM audio stream. The DAC recognizes the markers in the PCM stream that indicate it is DSD data and switches to DSD decoding mode.
3. Conversion to PCM: If a DAC does not support DSD or DoP, DSD files can be converted to PCM before being sent to the DAC. This conversion can be done by software players like JRiver Media Center, Audirvana Plus, or Foobar2000 with the appropriate plugins.

(this last sentence is from me  ) Whether the format is native DSD or DoP (which is still DSD), DACs that support DSD will decode correctly. Some player software simply converts DSD to PCM.

[Jargier]

Yes, I agree with the above. NuPrime DAC-9 will natively support DSD256 files. Does not natively support DSD512 - noise, silence or an error pops up. Player programs such as Audirvana automatically decode the signal into PCM and it enters the DAC. They do it perfectly. Some DACs decode the DSD signal (to a specific value, frequency) bit-perfectly on the fly. NuPrime only up to DSD256 values. In the Foobar2000 PC program, you need to manually set the DSD or PCM value in the SACD component. Therefore, for DSD512 and higher files, you should change the encoding from DSD to PCM in the Foobar program and set the maximum frequency value to 768kHz. Audirvana does this much better, but it is paid. Moreover, Windows (Foobar2000) handles streaming/sampling as it sees fit Linux-based computers handle it better. That's why I have the impression that Audirvana on MacOs sounds better.
​