Difference between revisions of "DSD"

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(Bitstreaming)
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==Bitstreaming==
 
==Bitstreaming==
  
It is also possible to bitstream DSD to certain DACs using ASIO 2.2, in which case the DSD to PCM conversion is not performed.
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It is possible to bitstream DSD to certain DACs.
  
Your DAC must support it.  Only a few do.
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There are multiple DSD bitstreaming technologies.
  
DAC's that support DSD include:
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'''ASIO 2.2'''
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This uses the native DSD support built into ASIO 2.2 to avoid DSD to PCM conversion.  Your DAC must support it.  Only a few do.
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DAC's that support DSD over ASIO include:
 
[http://playbackdesigns.com/ Playback Designs]
 
[http://playbackdesigns.com/ Playback Designs]
  
JRiver was part of forming an alternate DSD bitstreaming standard that does not require ASIO. This standard is called "DSD over PCM" or DoP for short.  JRiver is actively working with test hardware to add support for DoP.
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'''DSD over PCM (DoP)'''
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DSD over PCM packs DSD into a PCM-like signal to avoid DSD to PCM conversion.  This works in a similar way to how AC3 is packed into a PCM-like signal for S/PDIF surround sound output.
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JRiver was part of formation of the DoP standard.
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'''Enabling DSD bitstreaming'''
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To enable DSD bitstreaming, use Options > Video > Bitstreaming > Custom... and check:
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*DSD for ASIO 2.2 (requires ASIO)
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*DSD over PCM for DoP (requires WASAPI - Event Style)
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The option is under 'Video' because bitstreaming is traditionally a video option.
  
To enable DSD bitstreaming, use Options > Video > Bitstreaming > Custom... and check DSDThe option is under 'Video' because bitstreaming is traditionally a video option.
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With DoP, you can pick the marker format.  New hardware will use DoP 1.0 (0xFA/0x05)Older hardware may use the 0xAA marker format.
  
 
==DSD Sources==
 
==DSD Sources==

Revision as of 09:51, 14 March 2012

Overview

DSD is the format used for Super Audio CD's. Please see the article on DSD at Wikpedia more information.

Playback

By default, DSD will be converted to PCM for playback.

The DSD to PCM conversion process converts from 1-bit DSD to 64-bit PCM at 1/8th of the sample rate. The total amount of data from this conversion grows by 8x, so the process is effectively lossless / perfect.

Once you have PCM, it will be 64bit @ 352.8 kHz for DSD, and 64bit @ 705.6 kHz for DSD 2x.

It is rare for hardware to support these high sample rates, so downsampling is required. The option 'Greater than 192kHz' in DSP Studio > Output Format is what is used. There is no way to configure DSD 1x and DSD 2x independently.

A low pass filter at 30 kHz with a 24 dB/octave slope is used to remove the (basically) pink noise present in the upper frequency with DSD.

Bitstreaming

It is possible to bitstream DSD to certain DACs.

There are multiple DSD bitstreaming technologies.

ASIO 2.2

This uses the native DSD support built into ASIO 2.2 to avoid DSD to PCM conversion. Your DAC must support it. Only a few do.

DAC's that support DSD over ASIO include: Playback Designs

DSD over PCM (DoP)

DSD over PCM packs DSD into a PCM-like signal to avoid DSD to PCM conversion. This works in a similar way to how AC3 is packed into a PCM-like signal for S/PDIF surround sound output.

JRiver was part of formation of the DoP standard.

Enabling DSD bitstreaming

To enable DSD bitstreaming, use Options > Video > Bitstreaming > Custom... and check:

  • DSD for ASIO 2.2 (requires ASIO)
  • DSD over PCM for DoP (requires WASAPI - Event Style)

The option is under 'Video' because bitstreaming is traditionally a video option.

With DoP, you can pick the marker format. New hardware will use DoP 1.0 (0xFA/0x05). Older hardware may use the 0xAA marker format.

DSD Sources

Blue Coast Records

http://www.ps3sacd.com/dsd_downloads.html

Ripping Super Audio CD's

Article at computeraudiophile.com on ripping SACD's on an old PS3.