Dsd Full Scale; Dsd Mute; Dsd Overload Behaviour; Dsd Electrical And Data Structures - DCS 905 User Manual

dCS 905 User Manual
dCS Ltd

DSD Full Scale

DSD Mute

DSD Overload Behaviour

DSD Electrical and Data Structures

Manual filename: dCS905 Manual v1.0x Eng.doc
English version
Filter Comments
1 High SQNR,
high stability
2
High SQNR
3 High SQNR,
very high
stability
4 Extremely high
stability
5 Reduced 100k
noise
6
Single
complex zero
7 Real zeros
SACD Spec
Table 13 – DSD Filter Performance
The SACD standard sets 0dB0 for programme material 6dB below the peak to
peak level one might expect a full scale sinewave to occupy. This ensures that
artefacts that begin to occur at the limits of the DSD frequency range stay well
away from the audio band, and is shown in
905 complies with this standard. If the unit is set up for full scale PCM, and then
switched to a DSD format, the levels will be correctly set to meet SACD
standards.
A DSD mute is unlike a PCM mute (which is 00000....), because with only two
levels, there is not a single value that sets the output in the middle of the range.
In all DSD formats except P3D, the dCS 905 outputs 010101010101.... as a
DSD mute. For P3D it outputs 01101001 as a P3D DSD mute.
DSD is more benign than PCM under overload conditions. In the overload
region, the performance gradually and gracefully degrades. The size of this
region depends on the modulator used, but in general, a modulator with a
higher stability will allow a larger overload region (see
region may be several dB. In the dCS 905, the signal level is digitally clamped
about 1.5dB above SACD 0dB level.
dCS modulators recover from overload rapidly
Electrically, for the SDIF-2 and SDIF-3 outputs, TTL levels are used. There is
no framing or block structure, and each channel uses one BNC connector. The
clock (word or bit clock) uses the third connector.
SQNR SQNR
(20kHz, (
F weighted,
dB) dB)
126.14 136.56
127.23 138.76
124.66 134.38
122.07 129.91
122.27 130.14
110.78 151.02
101.5 132.41
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Figure
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Page 67
Manual for Software Issue 1.0x
November 2006
E2 spec E3 spec
(dB) (dB)
-25.98 -28.96
-25.85 -28.95
-27.32 -30.49
-25.54 -29.53
-27.13 -31.99
-25.19 -23.55
-25.29 -27.04
-20.00 -28.00
34, on page 68. The dCS
Table 12). The overload
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