• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Odd hum problem

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
I have an Antique Sound Lab MG-s115 that has a strange hum
problem. This amp has a built in volumn controle. When the volumn controle is at 1/2 rotation I have maxium hum, turn it
up louder and the hum decreases ! Any idea what would cause
this?

Thanks,
Woody
:xeye:
 
Administrator
Joined 2004
Paid Member
Hi Woody,
The volume control presents the maximum impedance to the input circuit around 1/2 resistance. A load on the input (source like a CD or buffered preamp) would reduce or eliminate this.
You can also try shielding the volume control and leads. Also watch where your input wires run from the jack to where ever.
-Chris
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.