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While waiting for parts to be in stock I have ordered a DAC that doesn't have the best jitter specs in the world. It is the E-MU 0404 USB and has a PLL that is < 500ps rated. Once I can get TP parts it will be a second setup. My question is, would the chain above be useful for jitter rejection? IS there reason to think that it would end up reducing jitter in the DAC?
Thanks,
v
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I looked through the WM8804 Datasheet and have the following for jumper settings. Would appreciate a correction if they are wrong
First 8804:
AIF/MS - 1 (master mode)
TXSRC - 0 (SPDIF in)
AIFCONF1 - 0
AIFCONF0 - 1
-> Metronome ->
Second 8804:
AIF_MS - 0 ( slave mode)
TXSRC - 1 (I2S in)
AIFCONF1 - 0
AIFCONF0 - 1
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Still thinking about making a clock box. Original idea was WM8804 -> metronome -> WM8804.
Now I am wondering if I could *omit* the first WM8804 and let the metronome go without I2S input. If I set it to a certain frequency, say 24bit 96 kHz will it put out the proper clocks to interface with the second 8804? The signal doesn't matter to me, just the clock.
v
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So you want to receive SPDIF -> reclock -> Send SPDIF?
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Pretty Much. But I am thinking all I really need is generate clock (with metronome) -> send SPDIF. I want to use the metronome as a high precision SPDIF clock so the audio data doesn't matter at all. So I would operate the 8804 as slave mode like above. I am also hoping that I can remove the 8804 board clock without hurting anything.
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Well my feeling is this. It may help - but likely won't make a huge difference because SPDIF receivers usually use some form of PLL to recover a clock from the incoming signal. Still I suppose it would be a fun experiment. I have never tried doing it.
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Still need to know a few things. Will slave mode let the 8804 lock on and pass the SRC4192's signal? Do I need an input for the metronome? Or can I just go SRC4192(no input) -> 8804 SPDIF out Can I desolder the crystal from the 8804 that is operating in slave mode? Thanks! Edited by user Wednesday, October 14, 2015 6:02:07 PM(UTC)
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I can only refer you to the datasheets I really have not tried that scenario.
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