I get a real good hum out of the balanced output of the ubc01 when connected with a qsxm3
here is how my wires are connected.
Is your ground connected in your balanced wiring?
Pin 1 of the xlr is connected to the shield of the wire which connects to theground of the ubc01
If you disconnect one channel (the balanced output) does the hum disappear? I suspect that you have a massive ground loop.
if i disconnect one of the xlrs completely, yes it does
any suggestions of how to rewire my ground?
Try to identify how a ground loop is created.
By disconnecting one by one the grounds?
Yes. This should be quite visible.
I have tried all possible round combinations, and virtually no change.
However i released that if i remove the inputs from the qsxm3 and i put jumpers j1 and j3 it is dead silent.
what does this man? is it my turntable?
Your tone arm must be grounded via a separate wire to the QSXM3. Is that the case?
Yes its done. By the way the right channel has a louder hum than the left
Cartridge connected to the QSXM3 and then via unbalanced to the amp = no hum
Cartridge connected to the QSXM3 and then via balanced to the amp = hum
Shorted inputs of the QSXM3 and then via balanced to the amp = hum
Shorted signal into the UBC01 = no hum?
Is that the case?
ok tried everything again, i turned my transformer and puff hum disappeared, there is only a slight sinusoidal sound (much higher frequency than 50hz) but its down to the cartridge noise floor. I guess I can consider this normal?
unbalanced or balanced makes no difference, except that in balanced its more notable as all the volumes are louder anyway
with the outputs shorted now i get perfect silence
You mean inputs shorted?