It's the outboard variac that comes with and powers Joule Electra amps, specifically the VZN-80. It is supposed to stay at 85 volts during operation. I'm pretty sure it doesn't self-adjust.
I'm wondering if investing in a voltage regulator would help as my Belkin FP60 does reports incoming voltage drops when the stereo is playing and especially when the air conditioning kicks in (drops down to 116). Or even installing a dedicated line for the hifi gear?
The amp and variac are currently out for repair. The variac is shot and a new core is needed, although it might be cheaper to replace it altogether with a commercial product direct from variac corp. anyone have experience with that?