Author Topic: dsd file format conversion  (Read 3413 times)

bailso

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Hi All,

I understand that MB decodes these files on the fly to 88.2 khz / 24 ( or more) bit PCM files. Given the difficulty in tagging these files in the database, I thought there may be some merit in using the format conversion utility in MB to replace these DSD files with Wav or FLAC permanently.

I tried this and the resultant files showed a bitrate/sample rate of 1556/88 for FLAC and 2822/88 for Wav. I think that equates to a bit depth of 18 and 32 respectively. Given the limitations on my hardware I expected to see my DAC display sample rate / bit depth of 88.2 / 24 in each case as it does when MB does the conversion on the fly. However my DAC is displaying a bit depth of 16 on both the FLAC and Wav conversions. I used the "archive quality" option in each case during the DSD to FLAC abd DSD to Wav conversions.

Is there anyway to keep the bit depth of 24 while using the format conversion utility?

Regards

hiccup

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There is no way to 'keep the bit depth of 24bits' when converting DSD to flac (or any other codec), since DSD isn't 16, 24, 32 or whatever bit depth. Simply put, it's a whole different beast, and actually a 1 bit streaming algorithm.
So when you convert it to another format, you are actually transcoding, so you are changing the sound quality.
I believe MusicBee will transcode dsd to 16 bit bit depth. I am guessing it will probably keep the same sample rate as the original dsd file.
Other tools might have optional settings to transcode to 24 bit, or set required sample rates.

The values of 1556 and 2822 you mention are bit rates, not bit depths. They only say something about the average rate the file streams through your decoder (player).
It doesn't say anything about bit depth, sample rate, audio quality etc.
Well, of course a very high value might make it probable you are dealing with a 24/88 file, but you can not calculate anything from it.

vincent kars

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2 channel 16 bit word and a 88200 Hz sample rate = 2822.4 kbs

DSD is single bit indeed
Its dynamic range is approximately 150 dB, its frequency range about 100 kHz
 
16 bits is dynamic range of 96 db, 24 of 144 db
It might be interesting to experiment a little with the bit depth as 16 looks a bit small

DSD62 has a massive quantisation noise starting at  20 kHz
DSD 128 at the double of course.
The standard says filtering should be applied at 50 kHz
88 seems a fair PCM sample rate to me.

Some spectrums: http://www.thewelltemperedcomputer.com/SW/AudioTools/Spectrum.htm

hiccup

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2 channel 16 bit word and a 88200 Hz sample rate = 2822.4 kbs

Indeed, but such a calculation will only work for wav, not for flac.
And flac will probably be preferred, especially for the mentioned purpose of tagging.

bailso

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Thanks for your advice.
If anyone desires 24 bit depth and/or above 88.2 khz sampling rate on conversion of DSD files to PCM it appears one solution is to use Foobar 2000 to perform the conversion and then load the output files into MusicBee.
Regards to all