Only Transcode Higher Rated Music

[AnnieBody]

Hi
I am just trying some options for high level music playback.
My Cambridge Audio 851N streamer supports up to wav24 and dsd64, but I have some files with much higher rates. It currently plays all music without having a need to use a 'stream.transcoding' option.
Now, I know I can recode the music to play back on the 851N but I am working on a Raspberry Pi replacement of my Squeezebox and while doing so want to have the highest music coding for future proofing, and would like to compare the results.
Is there a way to set the transcoding for wav32 to wav24 without affecting other wav rates?
Is there a way to set the transcoding for DSD128, 256 and 1024 to preferably play as DSD64, or another format?
Regards

[simoncn]

You can do this for some file formats using input type filters (see this section) but there are limitations based on what FFmpeg supports.

To transcode wav32 (only) to wav24, you can set stream.transcode to: wav(32):wav24

You can't transcode DSD to DSD, only DSD to wav. This is an FFmpeg limitation. Transcoding DSD to wav would (in my experience) adversely affect sound quality for all resolutions.

[AnnieBody]

"You can't transcode DSD to DSD, only DSD to wav."

Then I am currently doing this for the DSD64 files, which, despite being transcoded still sound very good indeed!
As I have no transcode set I can only play DSD64 (to wav).
If I try and play higher rate DSD files they don't play. I assume this is because the default wav format for these files is wrong for my player.
So how would I transcode the higher rate DSD128,256 and 1024 files to the same wav format as the DSD64 wav?

[simoncn]

If you are playing DSD64 files as WAV, you must have something in stream.transcode to specify this. For example, is this setting

dsf:wav
dsf:wav24;176

or something else?

[AnnieBody]

I have nothing set in the stream.transcode options because I don't need to transcode files which my player plays.
You have advised DSD plays as wav even though my player advises the DSD64 file is playing as DSD64, not wav.
Assuming you are correct and my player is wrong, I want to know how to set the transcode for the higher level DSD files which currently don't play. I assume this is because the wav settings for DSD128 is different to that of DSD64. So how do I set the DSD128 wav to the same settings as that of the DSD64?

[simoncn]

There has been some misunderstanding. I have not said that MinimServer plays DSD64 files as WAV. You have two options for playing DSD files:

1) Leave stream.transcode empty. This plays all DSD files in their original untranscoded format.

2) Add a transcoding option to stream.transcode. For DSD files (of any resolution), this option must be set to transcode from DSD to WAV. It cannot be set to transcode from DSD128 to DSD64 (for example).

To transcode all DSD files of higher resolution than DSD64 to WAV 24/176, you can set stream.transcode to:

dsf(>64):wav24;176

If your player can play 32/352 PCM files, you could use the following setting:

dsf(>64):wav32;352

Choosing a suitable WAV resolution for this setting will enable you to play your DSD128 and higher files but it is likely you will notice a reduction in sound quality.

[AnnieBody]

Nearly there!
I now use:
dsf(>64):wav24;192, wav(>24;192):wav24;192

The DSF works a treat, but I am experiencing problems with the wav transcode.
My player only handles 24;192 as the maximum file type.
For sample rates up to 192 it correctly transcodes 32 bit to 24: great!

For sample rates above 192 my player just skips these tracks, so it appears to not be transcoding the samplerate correctly.
I tried:
wav(>24;>192):wav24;192
but this gives me an error.
What would be a correct transcode for this type of option?

What I am looking for is one entry to cover >24 to 24 AND >192 to 192 plus 24;>192 to 24:192
Would I need to enter a string of options or can this be achieved more simply?
Regards

[simoncn]

The setting wav(>24;192):wav24;192 is correct. I have tried this on a 24/352 WAV file and confirmed it is working correctly.

When you set this, you need to refresh the control point's view of the MinimServer library. Any files currently shown by the control point or in your playing queue will not have this setting activated. The way to do this refresh depends on your control point. For most control points, it is sufficient to browse up to the parent container and then browse down again to the file you want to play.

For transcoding DSF files, you might like to try dsf(>64):wav24;176. The native resolution produced by the FFmpeg DSF transcoder is 352.4 kHz and downsampling this to an exact fraction is generally considered preferable even though this is a lower numeric value.

[AnnieBody]

(10-06-2022 19:40)AnnieBody Wrote:  After rebooting my pc and player, I am able to play all formats except for 32:358.2 and 32:384.
I tried to to save a log playing a lesser track, then the first of the two above.
The 'debug' log showed the first track being played but did not show two tracks being attempted nor skipping two and playing the next in the queue.
What logging method should I be using?

It does successfully transcode 24:358.2 and 24:358.

[simoncn]

I tried transcoding 32-bit WAV to 24-bit and I am seeing the same problem.

I have identified what is causing this and a fix is available now in MinimServer update 216. If you restart MinimServer, this update will be installed automatically.

Thanks for letting me know about this problem.