digital output pcb mounting, is there a reason for it? wire to a chasis mount ok?

alamakazam

Member
2008-11-25 2:41 pm
I notice most dac have pcb mount digital output and place near to chassis,


if I were to DIY a dac , place the pcb in the middle of a chassis, I need to wire this output to the chassis? any problem? I have never seen digital output wired this way


thinking of using this mount to wire to the pcb

R3604992-25.jpg
 

wwenze

Member
2008-03-07 12:46 pm
The earlier it reaches the PCB the earlier it reaches the receiver chip and after that it can forget about keeping the required impedance. Additional connectors and terminations the signal goes through are additional potential sources of impedance mismatch and hence signal reflections.

Audio-gd products use wires between the connectors and PCB:
Audio-GD Company

And another one:
[IMGDEAD]http://www.vocativeaudio.com/DAC/matrix.mini-i.4.jpg[/IMGDEAD]

What is done in the above photo is correct - using cable and connector with the correct impedance. Using any 2 bare wires and soldering it straight to the PCB like what is done in the first link is a no-no.