On a circuit board with a mixer chip (and some auxiliary components like coupling capacitors), I have to lay a number of tracks (35 µ copper layer on epoxy substrate; max. track length: 120 mm). The amp is not part of this board. Neither is a DAC.
Now I'd like to know how wide tracks transmitting HiFi analog audio data (up to 20 kHz; including classical music) must be. Standard width would be 0.5 mm.
Here are my schematics and preliminary PCB layout. Please note that neither the 12V–to–5V converter, nor the Schmitt trigger have anything to do with the audio. They are just there because there is some space left over for them:
ORIGINAL FILES: If anybody is interested in the original Kicad files, please go to this folder: Mixer PCB