I doubt about that. I think that the 33.868MHz needs to be in sync with the incoming data from the optical block. Decopling it from the PLL would break the sync...
But the devil is not so black - the SM8707E (Denon DVD-2930, DVD-3930) doesn't have jitter that bad. Attached is a pic - part of the technical data. It has only 55ps!
PS: The SM8701 used in DVD-2910 has only 150ps jitter in the mode used in circuit, not 450ps!
But the devil is not so black - the SM8707E (Denon DVD-2930, DVD-3930) doesn't have jitter that bad. Attached is a pic - part of the technical data. It has only 55ps!
PS: The SM8701 used in DVD-2910 has only 150ps jitter in the mode used in circuit, not 450ps!
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Correct, that is just for output SO2 (256fs) and only in double mode (at 512fs).
For SACD(DSD), the SO1 (33MHz output) has 150ps. The PCM signal is further reclocked (and upsampled - only the 44.1 and 48kHz) in the DSP chip (ADSP 21266, 25MHZ XTALL) so I have the feeling that all the input jitter will be gone.
Anyway, the 2930/3930 have the newer chip 8707, with 55ps.
PS: I wonder if replacing the 8701 with 8707 wouldn't be something to try on a 2910? I have both 2930 and 2910 so I might try...
For SACD(DSD), the SO1 (33MHz output) has 150ps. The PCM signal is further reclocked (and upsampled - only the 44.1 and 48kHz) in the DSP chip (ADSP 21266, 25MHZ XTALL) so I have the feeling that all the input jitter will be gone.
Anyway, the 2930/3930 have the newer chip 8707, with 55ps.
PS: I wonder if replacing the 8701 with 8707 wouldn't be something to try on a 2910? I have both 2930 and 2910 so I might try...
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Actualy the dsp is loaded with a 18.5Mhz crystal (despite the manual)
Replacing with a sm8707 crossed my mind but is beyond my capabilities with all that smd stuff. Furthermore the 8707 has no 256fs output and the serial configuration must be the same. On second thought removing the voltage doubler (CY2302) solves the 256fs problem.
With the cy2302 output-one is used with 200ps, They had better used output-two with only 90ps.
I think the pcm signal for 88,2k and 96k for dvd is also processed by the dsp. (important for the audio section of dvd-video concerts and dvd-a).
The signal always goes through the dsp, (i don't know about dsd). So how important are the preceding steps?
Can one hear a difference between 3ps, 50ps and 150ps jitter? Difficult to determin if you don't have two identical machines to start with.
Replacing with a sm8707 crossed my mind but is beyond my capabilities with all that smd stuff. Furthermore the 8707 has no 256fs output and the serial configuration must be the same. On second thought removing the voltage doubler (CY2302) solves the 256fs problem.
With the cy2302 output-one is used with 200ps, They had better used output-two with only 90ps.
I think the pcm signal for 88,2k and 96k for dvd is also processed by the dsp. (important for the audio section of dvd-video concerts and dvd-a).
The signal always goes through the dsp, (i don't know about dsd). So how important are the preceding steps?
Can one hear a difference between 3ps, 50ps and 150ps jitter? Difficult to determin if you don't have two identical machines to start with.
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