There was a bug in the file: I miscalculated the number of samples by a factor of two. A DSD player can either ignore the stated number of samples and just play it properly or complain about a corrupt .dsf file. Hans's software just played it.
Anyway, attached is a corrected file and similar files for different DSD rates, all zipped. They all become about 1000 times as large when unzipped.
There are also two DSD128 files with periodic patterns representing large DC offsets, they are in plusmineenDSD128.zip. Whatever you do, don't play these at high volumes over completely DC coupled equipment! One of them has a periodic 11101110... pattern, that is, a positive offset of 0 dB DSD and the other a 00010001... pattern, corresponding to a 0 dB DSD negative offset.
Just in case it is of use to anyone: attached is a Pascal program that generates DSD512 .dsf test files with silence, an offset, or a sum of an offset and a sine wave, depending on what values you give the constants offsetL, offsetR, freqL, freqR, amplL and ampR at the beginning of the program. Mind you, when the sigma-delta modulator input signals are too large, you get a runtime error. The program's file extension is supposed to be .pp, but I've changed it into .txt to please the forum software.
Unlike the attachments of the previous post, the files this program generates have irregular patterns with noise-shaped quantization noise. It uses the very same algorithm I used for the PWM8 mode of my valve DAC, except that the code to prevent misbehaviour when the sigma-delta is overdriven is missing. It is a quasi-multibit sigma-delta modulator with an embedded pulse width modulator with randomly rotated output patterns, as explained here: https://linearaudio.net/sites/linearaudio.net/files/03 Didden LA V13 mvdg.pdf sections 3.1 and 9.
The program runs under Free Pascal Compiler. Whether it actually produces a valid .dsf file may depend on the endianness of your computer.
Unlike the attachments of the previous post, the files this program generates have irregular patterns with noise-shaped quantization noise. It uses the very same algorithm I used for the PWM8 mode of my valve DAC, except that the code to prevent misbehaviour when the sigma-delta is overdriven is missing. It is a quasi-multibit sigma-delta modulator with an embedded pulse width modulator with randomly rotated output patterns, as explained here: https://linearaudio.net/sites/linearaudio.net/files/03 Didden LA V13 mvdg.pdf sections 3.1 and 9.
The program runs under Free Pascal Compiler. Whether it actually produces a valid .dsf file may depend on the endianness of your computer.
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Hi Mark,
Good question, but since crosstalk between data and clock already seemed to play a role in this test, I was afraid of adding just another antenna and/or groundloop to the unshielded setup.
And since my goal was just testing and not listening, I didn’t use this option for which I’m sure that it may improve the listening experience.
But as you may have read in the review, I tried a double shielded very short USB interlink versus a very simple 1.5 meter USB cable and could not detect any difference.
Hans
Good question, but since crosstalk between data and clock already seemed to play a role in this test, I was afraid of adding just another antenna and/or groundloop to the unshielded setup.
And since my goal was just testing and not listening, I didn’t use this option for which I’m sure that it may improve the listening experience.
But as you may have read in the review, I tried a double shielded very short USB interlink versus a very simple 1.5 meter USB cable and could not detect any difference.
Hans
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That is not in dispute. The terms are. The idea of DOP to I2S is ridiculous. The payload for DOP is DSD data. I2S doesn't get a look in. And as for I2S DSD.........
There are alternatives to JRiver for DSD test signals.
Archimago's blog has some information on DSD test signals and how to generate them using sox. Also a download link for some test signals.
http://archimago.blogspot.com/2022/06/notes-on-dac-dsd-1-bit-pdm-measurements.html
Multitone Analyzer has DSD test signals and DoP output on Windows.
https://distortaudio.org/multitone.html
Archimago's blog has some information on DSD test signals and how to generate them using sox. Also a download link for some test signals.
http://archimago.blogspot.com/2022/06/notes-on-dac-dsd-1-bit-pdm-measurements.html
Multitone Analyzer has DSD test signals and DoP output on Windows.
https://distortaudio.org/multitone.html
Thx Bohrok,
Very interesting information on the archimago site.
In one of his reviews he compares several PCM to DSD options.
I was happy to see that JRiver came out as almost the best.
Also tried again to find out whether an official name exists for DSD after being split into Left, Right and Clock, but no succes.
In this world with so many acronyms this seems to be the one that's missing.
I'm sorry when using the term I2S DSD caused any confusion.
Hans
Very interesting information on the archimago site.
In one of his reviews he compares several PCM to DSD options.
I was happy to see that JRiver came out as almost the best.
Also tried again to find out whether an official name exists for DSD after being split into Left, Right and Clock, but no succes.
In this world with so many acronyms this seems to be the one that's missing.
I'm sorry when using the term I2S DSD caused any confusion.
Hans
SDIF (SDIF-2 DSD and SDIF-3) might be it. It's based upon separate 75 ohm BNC cables for left/right/clock.
dCS support article: https://dcsaudio.zendesk.com/hc/en-gb/articles/360015051300-What-is-an-SDIF-2-interface-
Sony paper from 1999: https://www.grimmaudio.com/wp-content/uploads/sdif3v10.pdf
dCS support article: https://dcsaudio.zendesk.com/hc/en-gb/articles/360015051300-What-is-an-SDIF-2-interface-
Sony paper from 1999: https://www.grimmaudio.com/wp-content/uploads/sdif3v10.pdf
So the relevant name is Composite DSD according to you.
Here is a link, happy reading.
https://www.dsdcomposites.com/
Hans
Here is a link, happy reading.
https://www.dsdcomposites.com/
Hans