DSD: pourquoi et comment?

[Janacek]

ICi en peu de lecture selon Bel Canto pour le DSD et DoP

http://www.belcantodesign.com/pdfs/Optim...ayback.pdf

Citation :DSD is a very hot topic right now in digital. We are aware of the format and

all the titles soon to be released. Our goal is to make sure you get the most

satisfaction from all of your digital source material, especially DSD, now that

it’s back in the news.

There are optimal ways to listen to DSD that insure the best sonic

performance, and all of our current DAC products provide the performance

you desire from any of your digital source files, DSD, 16/44.1 PCM and high bit

rate PCM.

It’s important to remember DSD format occurred in early days of digital

reproduction. As you’ll see in the examples at the end of this paper

PCM is much quieter, with a larger dynamic range. So it captures all of

the performance of the original DSD signal. By following our conversion

recommendations the result will be superior playback of DSD material

without compromising any digital format.

With a bel canto DAC you will always be on the forefront of digital because
high dynamic range performance is designed in from the beginning

Citation :All Bel Canto DACs can be used to play DSD files perfectly by using JRiver, Pure Music

or other software

. This is accomplished using the computer for conversion from DSD
to a 24/176.4 PCM file and streaming this through the USB interface. We prefer this
method for optimum playback of DSD for the following reasons:
1)
All State-of-the-Art DACs are either multi-bit sigma-delta, 24 bit PCM or a
combination. These modern DACs can provide very high dynamic range, low
noise and distortion with performance approaching 126-128dB. Either PCM or
DSD source files will be converted to whatever specific modulation method the
DAC uses for final conversion to analog.


What this means is that there is NO ‘pure’ DSD playback method using a modern high
performance DAC.

2)
DSD has very high noise levels above 20 kHz because of the noise-shaping
algorithm
used to achieve reasonable noise levels in the lower audio
frequencies. This noise needs to be reduced by the addition of either an
analog filter stage if playback remains DSD or an FIR filter if playback uses a
conversion to PCM.
Any additional analog filters add noise and distortion
, the
PCM FIR filter avoids the need for any additional analog circuitry.
This is the primary reason we prefer DSD playback using conversion to 24/176.4 PCM.


There is no additional analog circuitry needed that would compromise the final
output.

3)
The PCM conversion process that JRiver and Pure Music provide uses 64 bit
math and is transparent,
adding no additional noise or distortion products,
indeed the noise shaping characteristic of the DSD file is retained as shown
in figures 1 and 2.
Any sound characteristics that this noise floor offers will be
retained and heard through the final analog output

4)

24/176.4 PCM is inherently a lower noise, wider dynamic range process than

DSD

so playback of the DSD file within the PCM process will not add any

distortion or noise to the original DSD signal.

The beauty of the conversion to 24/176.4 PCM is that all of the characteristics of the

original DSD file are retained

and you can get the sound characteristics of DSD

without compromise to playback of any PCM files, either CD or at higher bit rates of
24/88.2 and above.

Il y a aussi des graphismes.