Coax output circuit (SPDIF)

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All,

I am now using my Denon 2800 with an external DAC. I have the service manual for the Denon and have been looking at the coax output circuit. I noticed that the spdif signal passes through some inverters, transformers, caps, inductors, etc. before it reaches the coax RCA-type jack.

I am only running 1M of Monster M1000D digital cable, and was wondering if the digital output circuit of my Denon can be improved.
In it's simplest form, I've seen a schematic online where only 1 cap and two resistors (1 in series, one in parallel) were used (I guess to convert TTL to SPDIF). Is this a case of "simpler is better" or are all the buffers and EMI stuff in the path benefical to the digital dignal. Put another way, would a simpler circuit add or reduce jitter and other eye pattern parameters like Extinction Ratio, overshoot, etc.

Also, if a 75ohm impedance cable is important, then why does the signal pass through crappy PCB traces and connectors before it reached the jack. Isn't this messing it up somewhat? :scratch:

Thanks for all your input,

Vinnie
 
This has been discussed before. Look especially for some comments from Jocko about how to do things right.

Short form:
Get rid of the RCA and use a 75 ohm BNC
PCB traces don't have to be controlled impedance b/c they aren't transmission lines
A quality pulse transformer is a good thing
Be careful how you terminate your cables or you'll blow your savings
 
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