Hi guys,
can I ask you a quick advice?
I built a 4 channel buffer with two B1 boards and two Biino boards as potentiometers...
The problem is that now I hear a 50hz (I guess) hum coming from speakers... It's not loud at all, but it's there...
Some facts:
- in the buffer the signal ground is not connected to earth
- if I disconnect earth from buffer case, noise is still there
- if I disconnect earth from buffer and the two amps behind, noise is still there
- if I connect signal ground to earth in the buffer, noise is still there
- if I SWITCH OFF the buffer and switch on the amps, the noise is a little lower, but still there
- there's a DC filter on the ac mains that feed buffer and amps
Can you guess maybe where to look better?
Thank you so much, guys!
can I ask you a quick advice?
I built a 4 channel buffer with two B1 boards and two Biino boards as potentiometers...
The problem is that now I hear a 50hz (I guess) hum coming from speakers... It's not loud at all, but it's there...
Some facts:
- in the buffer the signal ground is not connected to earth
- if I disconnect earth from buffer case, noise is still there
- if I disconnect earth from buffer and the two amps behind, noise is still there
- if I connect signal ground to earth in the buffer, noise is still there
- if I SWITCH OFF the buffer and switch on the amps, the noise is a little lower, but still there
- there's a DC filter on the ac mains that feed buffer and amps
Can you guess maybe where to look better?
Thank you so much, guys!
