DSD Playback Options - Feature Request for the Wiim Ultra

[Alex Dunavski]

Feature request, in the order of descending preferences. Thank you very much for your anticipated related efforts:

(A) Implement a native DSD playback, or native using DoP. Note: If that may significantly reduce the DSP capabilities of the Ultra, that would be understandable. If that may not be possible, then ...

(B) Add the following to the Ultra's current DSD-to-PCM capabilities:
- Remove the ultra-sonic noise starting from about 30 to 35kHz and up. Note: The ultra-sonic noise is currently present, and can only make the downstream equipment work harder without any benefits.
- Increase the signal loudness by 6dB, or close to 6dB. If with 6dB the avoidance of the signal clipping may be difficult, make the increase of the signal loudness user-selectable, e.g. +3dB, +3.5dB +4dB, +4.5dB, +5dB, +5.5dB, +6dB.
- Convert DSD to PCM with the 88.2kHz or 176.4kHz sampling frequency, rather than the currently used 192kHz.

 

[s3igell]

While some WiiM personnel do surf the User Forum on a frequent basis, the Official method to post a Feature Request is via the WiiM Home App (More / Feedback). Go for it!!
(I've an interest in DSD Playback, too.)

 

[SoFluffy]

I too would love all of these improvements/features. I'll add that I'd also want WavPack (.wv) to be supported, as that cuts the .dsf file size by about 50% while maintaining lossless DSD. (WavPack losslessly compresses DSD much more efficiently than converting .dsf to DOP flac, in case anyone was wondering as I did.)

Even if A isn't possible, the suggestions from B are solid.

 

[Indydan]

I believe the Wiim amp ultra is not DSD compatible. I have noticed though, that it still plays my DSD files. It seems to convert them to PCM?

 

[hgo58]

I believe the Wiim amp ultra is not DSD compatible. I have noticed though, that it still plays my DSD files. It seems to convert them to PCM?

Yes it does.

Playing DSD Audio Files on WiiM Devices

All WiiM devices, except for the WiiM Mini, support DSD audio file playback. These devices convert DSD content into PCM data for playback, with a sample rate of up to 192kHz. Here are the ways you can play DSD audio files on WiiM devices: ...

faq.wiimhome.com

This is to allow volume control and EQ, that is not directly possible with the DSD format.

 

[SoFluffy]

Correct. It's possible to use DOP and then an external DAC (with all EQ off and at 100% volume) to get pass-through DSD, assuming the DAC supports DOP. The issue here is that this is only possible if feeding the WiiM with a DOP source (Roon, flac files pre-encoded to DOP, etc). The WiiM cannot read a .dsf file and then output as native DSD (even if no EQ or volume). This is "option A" in OP's post.

For "option B", the WiiM can convert DSD to PCM on the fly, but does so at 192kHz. As @Alex Dunavski suggested though, the conversion to PCM should be a multiple of 44.1 for the sampling rate (probably 176.4kHz), and be raised by +6dB. And then there should also be a low pass filter to get rid of noise above ~30kHz that might be present when using PCM sampling rates 88.2kHz and higher. DACs will do this filtering automatically when decoding DSD, but won't with PCM. (Someone keep me honest here if that is the exception or the rule.)