mod NAD C520 (I'll add spdif input)

[hehe31]

Hi everyone

I want to improve the sound quality of my computer:
I just have a old Fortissimo II sound card (whith a spdif output), linked to an NAD amp (2 cinch analogic link) and JMLab speakers.
I can't buy a better sound card or a nice dac, no money

But i have an old NAD C320 i don't use (the cd reader is tired and jump times to times). I want tu use the DAC there is inside (PCM1710U) whith my spdif output

This is the interesting part (from service manual)



We can see the cd driver (LC78621) connected to the dac with the 3 wires. The dac generate the clock and give it to the cd driver.
The Quartz for LC78621 is wired but there isnt the Quartz and capas (the clock come from the dac^^)

There is my project:


I add a CS8416 to decode spdif.
I remove the dac's quartz and use the clock from the 8416.
The 8416 can choose between 2 spdif input: 1 from the cd driver and 1 from outside (coax plug).
I add the quartz for the cd driver
I remove mute transistors (not in picture, just before stereo output), mute is controlled my an other chip.

I don't test this (waiting for 8416^^), but it's the 1st time i work with digital audio signals.
Do u think i forget something? will it work? (and sorry for bad english^^)

[hehe31]

Little mistake in the 2d picture: The RMCK signal from 8416 go to dac's pin 5, not 4 The pin #4 is disconnected now
(I can't edit?)

[geopapa]

Hi,
My friend I just want to ask you something. Looks like we have the same player (NAD C520). Could you just tell me the model of the pickup mechanism it has? I can only figure out that it is a SANYO.
If i buy it, is it easy to replace it myself (I'm a novice)

Thank u very much!