DSD-2-PCM -- proof of concept, test sample and source code here Options

[SebastianG]

The ZIP contains 4 files:
- dsd2pcm.jar (the converter written in Java, outputs raw 24/88 PCM, intel byte order)
- info.txt (contains some infos)
- test2822k.dsd (14 seconds, mono DSD, 5 megs)
- test44k.mp3 (conversion result)

have fun,
Sebi

Edit-2011: For the latest C/C++ source code see https://code.google.com/p/dsd2pcm/ It is released under the new BSD license. The attatchment to this post is still the first Java release.



This post has been edited by SebastianG: Dec 4 2011, 17:45

Attached File(s)

 dsd2pcm.zip ( 3.56MB ) Number of downloads: 2498

 

[vincefalks]

The noise is indeed a problem with the DSD format and, format-wise, something only improved by DSD128 (pushes it up twice as high) and furthermore with DXD (even less noise).

When converting to PCM, my opinion would be that one should have the option to be able to tweak such filter settings as they see fit. If ones objective would be to perform the most accurate "capture" (for lack of a better word) of what's from the original DSD signal (within the frequency range of your PCM output), you should be able to capture the whole thing, noise and all, if you wanted. Even if just for analysis and debugging.

[rpp3po]

The problem with the "most accurate capture" is that DSD players do 'know' that terrible amounts of noise are there and their analog low-pass probably reaches far enough down to compensate somewhat. PCM doesn't have this problem, a good 96 kHz DAC will roughly output at least 40 kHz of perfect analog bandwidth. This would be a capture of the full digital DSD signal, but probably not an accurate capture of the equivalent DSD low passed 'experience'.

The noise is indeed a problem with the DSD format and, format-wise, something only improved by DSD128 (pushes it up twice as high) and furthermore with DXD (even less noise).

Yes, solve the problem by wasting space for insanely high bitrates, to rescue this purely marketing motivated technology, instead of using proper PCM. DSD has not a single advantage over PCM other than DA converter costs. Good DSD DAC can be built pretty cheaply, kind of strange when you're targeting the higher end. But excellent PCM DACs are also available at commodity prices nowadays. Just accept it, the format is dead.

[vincefalks]

The problem with the "most accurate capture" is that DSD players do 'know' that terrible amounts of noise are there and their analog low-pass probably reaches far enough down to compensate somewhat. PCM doesn't have this problem, a good 96 kHz DAC will roughly output at least 40 kHz of perfect analog bandwidth. This would be a capture of the full digital DSD signal, but probably not an accurate capture of the equivalent DSD low passed 'experience'.

No, that's right. But to someone who wants as full a picture (mathemaatically) of the original DSD signal should have access to everything if they want. And then filter it out later if they want.

The noise is indeed a problem with the DSD format and, format-wise, something only improved by DSD128 (pushes it up twice as high) and furthermore with DXD (even less noise).

Yes, solve the problem by wasting space for insanely high bitrates, to rescue this purely marketing motivated technology, instead of using proper PCM.

Well, I have no comment on that here , but if you were to stay within the DSD "family", those are the "solutions" to the noise problem (although DXD is in its own new category, or you might say it's within the PCM "family" - it is PCM-*based* but with a relaxed anti-alias filter giving it properties/elements of the DSD encoding scheme).

DSD has not a single advantage over PCM other than DA converter costs. Good DSD DAC can be built pretty cheaply, kind of strange when you're targeting the higher end. But excellent PCM DACs are also available at commodity prices nowadays. Just accept it, the format is dead.

I have no comment about the value of DSD other than that I value it for reasons such as this: we have quite a lot of music mastered and released in the format, and some of it on non-hybrid discs. I happen to value this unique high quality catalog of music (and even on non-hybrid discs, there is the multichannel mix not available on the redbook layer) and thus am interested in converting this music to PCM in the purest way possible.

This post has been edited by vincefalks: Nov 24 2009, 14:29

[Canar]

I happen to value this unique high quality catalog of music (and even on non-hybrid discs, there is the multichannel mix not available on the redbook layer) and thus am interested in converting this music to PCM in the purest way possible.

I'd suggest keeping the originals as un-converted DSD and just decode to PCM on the fly using a foobar2000 component or something. I'm not sure that one exists currently, but having a library of lossless DSD material is probably preferable to the same material in PCM-decoded form. One less source of loss...

[rpp3po]

Raw DSD means saving about 3 GB per 70 minute stereo album. Kind of a waste when you can save 48kHz files, that should perfectly* preserve the 0-22 kHz band, and only need about 475 MB (FLAC). That's over 2.5 GB wasted, not for discarded but inaudible recorded information but plain quantization distortion, added by an inferior form of digitalization. Why save 2.5 GB of garbage per album? Has there ever been just one solid positive blind test for DSD?

* talk about differences of -110db or lower

This post has been edited by rpp3po: Nov 24 2009, 17:25