ProtoDAC TDA1387 X8 project

[thomaschan]

I think it would be best to decrease that I/V resistor as much as possible, as long as there is enough gain from the circuit. Distortion of the DAC will reduce with a lower I/V resistance, and it's always best not to amplify distortion. Also speculating that a metal foil (TX2575) resistor would be of value there.

Regarding a tube DAC for a CD transport, the inexpensive DIR9001 boards (SPDIF to I2S) work very well, in my experience.

Yes, I do find the gain is a bit too much with 90 ohm resistor. I will be tuning this resistor value.

As for receiver chip, I am planning on CS8412. Both Audio Note and Lampizator use this particular one. I do plan on trying CD4398 and AD1865 besides 1387.