For the last little while, I've been having an awful case of alternator whine. When the empeg was out of sled, I got none. When the empeg was off, I got none. When the empeg was on (even paused), I got the whine. I discovered that one of the -ve speaker wires had come apart, and was no longer connected. A few weeks ago, I spent some time soldering all the wires onto the connectors (as opposed to just crimping). That didn't work. Today, I checked the grounding. There was still a lot of paint between connector and frame, so I sanded that down to bare metal. Still no luck. I gave up, and put everything back together.

After that, I decided to adjust the gains on my amps, since they were far too loud for normal listening -- most of the time, I had the empeg volume nearly as low as it will go. After adjusting the gains, and turning the empeg up a bit closer to 0dB (well, it's now just past the middle, so that I still have some room to go up, if needed), I seem to no longer hear any whine. Empeg out of sled, no whine. Empeg off, no whine. Empeg on and paused, no whine. Empeg playing, no whine.

So... does this make sense? Did the previous position on the gain controls just mean that the electrical sensitivity was such that the extra whatever from the alternator was causing problems? The problem seems "fixed", but is it really just "masked"?

(Pardon my lack of use of appropriate terminology, but I don't really know anything about electrical systems. )