05-10-2018, 05:47 PM
I mentioned this over in Workshop in passing, but I though I would start a thread about it.
My Reverbrocket (a '61, blue sparkle, 6v6) has a 60Hz hum. It's not coming from the input stage - it's not volume dependent. It's not coming from the power tubes - when I pull the PI the amp is dead quiet. Just based on the audible frequency, I'm pretty sure that it's not 120Hz from the filtered high-voltage side of things. Sounds more like heater-cathode leakage.
I just discovered that the hum disappears when I activate the trem with the foot switch. I assume this is a ground loop, and I'll be chasing after it, but does anyone have any useful observations that might save me some time?
My Reverbrocket (a '61, blue sparkle, 6v6) has a 60Hz hum. It's not coming from the input stage - it's not volume dependent. It's not coming from the power tubes - when I pull the PI the amp is dead quiet. Just based on the audible frequency, I'm pretty sure that it's not 120Hz from the filtered high-voltage side of things. Sounds more like heater-cathode leakage.
I just discovered that the hum disappears when I activate the trem with the foot switch. I assume this is a ground loop, and I'll be chasing after it, but does anyone have any useful observations that might save me some time?