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DSD is it of any value

SpyB

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I would like to ask,if we send a DSD file to a DAC and we want to control the volume at the DAC,

it has to be converted to PCM.

So what is the point,we may just as well send a Hi Res PCM file to the DAC,

what is the value in a DSD file
 

pozz

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I would like to ask,if we send a DSD file to a DAC and we want to control the volume at the DAC,

it has to be converted to PCM.

So what is the point,we may just as well send a Hi Res PCM file to the DAC,

what is the value in a DSD file
It's another means of encoding signals. DSD is the marketing name, while the technique is called pulse density modulation ("PDM"). PDM is a stream of single bits processed at a much higher sampling rate. The advantages of PDM over pulse code modulation ("PCM") are to do with ease of implementation in the electrical domain and lower noise and distortion, while multibit PCM signals allow for ease of processing into complex operations like summing or filtering at the cost of higher noise (e.g., quantization noise).

This divide was relevant when the CD was invented and the trade-offs between techniques large. It is not relevant today. Note that every single DSD release out there (unless it's some kind of single-take affair like direct-to-disc vinyl recordings were once hyped) will have massive noise-shaped ultrasonic noise due to the fact that the bitstream needs to be converted to PCM for editing, mixing and mastering, and then reconverted to DSD.

PDM is still used commonly used in low cost/limited purpose ADCs such as cellphone microphones.
 

cjfrbw

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DSD was originally invented by Sony to archive crumbling analog tape libraries, because it preserved the analog pulse character of the sound. Sony was on it's one bit missionary zeal at that time, too. Commercializing DSD was an afterthought.

DSD needs quite a bit of noise shaping and proprietary algorithms as a playback medium. Sony made these sort of syrupy and nice sounding to accentuate the 'analog' character of DSD on playback. It works for some people, but I never found it completely convincing.

Standard SACD has increasingly lower bit playback above 8 khz, so standard CD Redbook has better high frequency reproduction. The claims of extended frequency response for SACD never explained this heavy bit drop off as the frequency went up. I found that I prefer PCM because the SACD playback is a bit strange to my ear for some reason.

Also, claimed DSD disks often had a lot of undisclosed cross contamination from PCM and non-analog sources. It was very difficult to edit DSD, so often editors would convert to PCM for editing, then back to DSD for masters. What was 'pure DSD' or not hasn't always been clear, and it seems consumers were often just paying for the syrupy sound of the playback noise shaping and algorithms.

Maybe all that has changed since with higher bitrate DSD, but SACD is mostly a specialty niche. I think the ultra hi rez PCM and improved digital in general have made DSD and SACD a bit redundant.
 

Kal Rubinson

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Are the same recordings available in PCM?
Sometimes, I guess. Of course, you can convert them if you wish but that would not resolve the objections of those who believe it is a flawed medium.
 
OP
SpyB

SpyB

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It's another means of encoding signals. DSD is the marketing name, while the technique is called pulse density modulation ("PDM"). PDM is a stream of single bits processed at a much higher sampling rate. The advantages of PDM over pulse code modulation ("PCM") are to do with ease of implementation in the electrical domain and lower noise and distortion, while multibit PCM signals allow for ease of processing into complex operations like summing or filtering at the cost of higher noise (e.g., quantization noise).

This divide was relevant when the CD was invented and the trade-offs between techniques large. It is not relevant today. Note that every single DSD release out there (unless it's some kind of single-take affair like direct-to-disc vinyl recordings were once hyped) will have massive noise-shaped ultrasonic noise due to the fact that the bitstream needs to be converted to PCM for editing, mixing and mastering, and then reconverted to DSD.

PDM is still used commonly used in low cost/limited purpose ADCs such as cellphone microphones.

Excellent explanation and very helpful, as are the other posts
Thank you
 

ahofer

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I have come to think of hi-res and DSD as like David Lee Roth's brown M&Ms - Unnecessary, probably, but it signals that the other quality measures might have also been prioritized in the recording process, and it is less likely to be another entry in the loudness wars.
 

Thomas savage

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I have come to think of hi-res and DSD as like David Lee Roth's brown M&Ms - Unnecessary, probably, but it signals that the other quality measures might have also been prioritized in the recording process, and it is less likely to be another entry in the loudness wars.
That would be awesome if it were true, at least it can make you feel good to think it though.
 

Wombat

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DSD was originally invented by Sony to archive crumbling analog tape libraries, because it preserved the analog pulse character of the sound. Sony was on it's one bit missionary zeal at that time, too. Commercializing DSD was an afterthought.

DSD needs quite a bit of noise shaping and proprietary algorithms as a playback medium. Sony made these sort of syrupy and nice sounding to accentuate the 'analog' character of DSD on playback. It works for some people, but I never found it completely convincing.

Standard SACD has increasingly lower bit playback above 8 khz, so standard CD Redbook has better high frequency reproduction. The claims of extended frequency response for SACD never explained this heavy bit drop off as the frequency went up. I found that I prefer PCM because the SACD playback is a bit strange to my ear for some reason.

Also, claimed DSD disks often had a lot of undisclosed cross contamination from PCM and non-analog sources. It was very difficult to edit DSD, so often editors would convert to PCM for editing, then back to DSD for masters. What was 'pure DSD' or not hasn't always been clear, and it seems consumers were often just paying for the syrupy sound of the playback noise shaping and algorithms.

Maybe all that has changed since with higher bitrate DSD, but SACD is mostly a specialty niche. I think the ultra hi rez PCM and improved digital in general have made DSD and SACD a bit redundant.


I would like to see some validated, generally repeatable, tests that confirm the syrupy sound statement.
 

PaulD

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I did do a blind test in a studio with the Korg MR-1000 DSD recorder when it came out, signal split after the mic preamps and sent to the Korg recorder and also to Avid Protools PCM converters at 24bit 96KHz. Level matched on playback, there was no audible difference between the DSD and PCM version.

Given the aggressive noise shaping required by DSD to make it work, and the fact that it cannot be edited or processed (even volume change is impossible) unless converted to PCM, I can see no value in DSD at all now. When DSD was developed PCM was stuck at 16bits and 48 KHz and perhaps it had an audible (or archival) advantage over that format of PCM, but today we routinely have 24bit 96KHz PCM which has none of the disadvantages of DSD, it has more resolution than we can hear and it can be edited and processed easily.
 

Spocko

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I would like to see some validated, generally repeatable, tests that confirm the syrupy sound statement.
"syrupy sounding" = high levels of 2nd order harmonic distortion? So maybe see if there are differences in that slice of data points.
 

Wombat

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"syrupy sounding" = high levels of 2nd order harmonic distortion? So maybe see if there are differences in that slice of data points.

Uh-huh.

Standard definition? Confirming measurement parameters and methods? You need to do better in putting your view forward in public.

I am interested.
 

bravomail

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I would like to ask,if we send a DSD file to a DAC and we want to control the volume at the DAC,

it has to be converted to PCM.

So what is the point,we may just as well send a Hi Res PCM file to the DAC,

what is the value in a DSD file

study the history of DSD. When it was introduced. Who introduced it. Why it was introduced. Check how many records r released purely in DSD vs "other conventional formats".

First was CD, then came PCM. Then came MP3. Then came DSD - cannot be converted/pirated easily/directly/digitally to MP3 due to high degree of ultrasonic noise. Introduced and marketed by Sony as "superior to all other formats". Which is simply not true - other formats, like PCM, take much less space in digital form and are easier to process (post-process) in audio editors. DSD is "write-only" format, as once you write it, it is hard to "read" it to do any processing - high degree of ultrasonic noise. DSD is incompressible and takes a lot of space. There are very few DSD releases compared to regular CD releases. Schiit company knowingly decided not to support such a schiity format. Chinese manufacturers involved in ongoing spec war with highest DSD rates.
 

thefsb

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Note that every single DSD release out there (unless it's some kind of single-take affair like direct-to-disc vinyl recordings were once hyped) will have massive noise-shaped ultrasonic noise due to the fact that the bitstream needs to be converted to PCM for editing, mixing and mastering, and then reconverted to DSD.

Is this also true of recordings made using DXD and converted to DSD only for distribution?
 
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