24bit sound in Musepack - possible or not?

[Marillion78]

Hello, all!

Please tell me is it possible to encode sound in musepack with 24 bit depth?

I saw a quote somewhere that

Currently only 32, 37.8, 44.1 and 48 kHz, 1-8 channels, 8-32 bit linear PCM is supported

I want to convert sound from VynilRip with 24bit/96Khz sound to musepack with the best able quality.

I use for it foobar2000, with DSP plugin Resampler (SoX), for resampling frequency to 48Khz as maximum from availaible (of course i would like to convert with 96Khz). Musepack version is SV8.

Here is my settings for converting in foobar2000:



But when converting is over, program MediaInfo shows that bit depth of resulting mpc files is only 16bit...

Is it really possible to convert in mpc with 24 bit (and 32bit) depth?

[Shy]

It is possible to encode 24-bit files. The resulting mpc file is a "lossy" file meant for playback and does not contain the amount of information that an uncompressed 24-bit stream can potentially contain.

The mpc file does not actually have "bits" (16-bit/24-bit, etc.) like an uncompressed file. Whether you get 16-bit or 24-bit decoding depends on the decoder, so when the player reports "16-bit mpc file" it actually means the decoder would give you a 16-bit stream, not that the file is actually a "16-bit file".

People don't set lossy format decoders to 24-bit since it would not offer any benefit compared to 16-bit with the lossy files. Lossy formats use "perceptual coding" and the only audible information that's left in the mpc file is that which you are able to perceive, and the rest is (crude explanation:) "thrown away" or "masked".
Although you hear no difference between the compressed file and the original, if you edit the compressed file, differences may be noticeable. For example, if you increase the volume by 40dB, you may hear artifacts that you wouldn't hear if you increased the uncompressed file's volume by 40dB. That's expected. The compressed stream is only suitable as a "final", "end-user" format and not meant to be altered.

Some tips:
In the case of a vinyl recording, the headroom is so low (amount of noise, crackle, etc.) that 24-bit does not enable you to preserve any more information than you would have been able to preserve with 16 bits of headroom. Merely the noise itself from the vinyl acts as a strong "dither" that makes 24-bit pointless.

I see you set the encoding quality to 10. You shouldn't do that, as it's a waste of space. Although quality 5 and 6 are very reliable (in being "transparent"), quality level 7 is the best balance between getting "assurance" that you get an artifacts-free stream and getting a file that doesn't waste a lot of space for no reason. In the extremely rare case that quality 7 does not sound identical to the original, higher quality settings would almost certainly not solve it either. Quality 10 is provided merely for completeness of the software.

[Marillion78]

Originally Posted by Shy

I see you set the encoding quality to 10. You shouldn't do that, as it's a waste of space. Although quality 5 and 6 are very reliable (in being "transparent"), quality level 7 is the best balance between getting "assurance" that you get an artifacts-free stream and getting a file that doesn't waste a lot of space for no reason. In the extremely rare case that quality 7 does not sound identical to the original, higher quality settings would almost certainly not solve it either. Quality 10 is provided merely for completeness of the software.

I chose musepack format as an intermediate variant between cbr mp3 320Kbps and lossless format, for archive storage and for playing on computer, but with the expectation that sometimes it may be need to transform musepack files to mp3-format for playing in hardware players that don't support musepack codec. It's not recommended to transform from one lossy file to another, but when transcoding from high bitrate musepack files, there is no hearable difference between when you transcode from lossless format. That's why i choose parameter q10 in mpc-encoding.

If i encode music from original to musepack with q6 or q7 quality, and then transform musepack file to mp3 with 192kbps bitrate, does the difference in quality will be noticed between the same mp3-file, but maded from original sound?

[Shy]

No, and since the 192kbps mp3 file would be of so low quality, it wouldn't matter whatsoever in any case.

[Marillion78]

Originally Posted by Shy

No, and since the 192kbps mp3 file would be of so low quality, it wouldn't matter whatsoever in any case.

And in case of transforming to 320Kbps cbr mp3 from musepack q5, q6, q7, and from original sound, would the difference in quality of 320Kbps mp3 be noticed?

[Shy]

In any case, it's impossible to get away from mp3's limitations like transient smearing even at 320kbps, but I suggest that you just listen for yourself to make your own decisions when it comes to sound quality.