Hi everyone!
So here a link to the test generated by right audio mark:
http://membres.lycos.fr/blendinpulse/adat/test/DIGI32_8 Out (1+2)(1)_9.htm
there are previous tests in http://membres.lycos.fr/blendinpulse/adat/test, but this one is the last one. I move the dac far from the psu to decrease noise level.
As you can see, there are, I think, harmonics, 50/100/150/200/250/300/350/400/450/500/550Hz... and I would like to know where they come from? anybody as an idea?
I also have another problem : when I put a TRS jack in the output and plug it in the input, it seems that there's a lot of noise, I have to touch the TRS metal case and then everything is fine (so yes during test my hand is on the TRS
). When I plug my amp on the convertor, can hear digital noise in the speaker : if i increase amp colume, the noise doesn't increase, and if I touch the output jack, or the cable going thru the amp, the noise disapear... any idea? I think it's because the digital ground of pcb is not connected to the case by the skrew (the analog and digital ground are seperate on the psu PCB, but I start to think of another psu for digital, with a seperate transformer).
thank you!
Pilo
So here a link to the test generated by right audio mark:
http://membres.lycos.fr/blendinpulse/adat/test/DIGI32_8 Out (1+2)(1)_9.htm
there are previous tests in http://membres.lycos.fr/blendinpulse/adat/test, but this one is the last one. I move the dac far from the psu to decrease noise level.
As you can see, there are, I think, harmonics, 50/100/150/200/250/300/350/400/450/500/550Hz... and I would like to know where they come from? anybody as an idea?
I also have another problem : when I put a TRS jack in the output and plug it in the input, it seems that there's a lot of noise, I have to touch the TRS metal case and then everything is fine (so yes during test my hand is on the TRS
). When I plug my amp on the convertor, can hear digital noise in the speaker : if i increase amp colume, the noise doesn't increase, and if I touch the output jack, or the cable going thru the amp, the noise disapear... any idea? I think it's because the digital ground of pcb is not connected to the case by the skrew (the analog and digital ground are seperate on the psu PCB, but I start to think of another psu for digital, with a seperate transformer).thank you!
Pilo
