I forgot I had my deck speakers on the other night and was playing some tunes, after a bit I noticed an odor and the tunes quite, it was at that point I realized the magic smoke was coming out of my power amp!

My deck speakers are 8 ohm and my Legacy's are 4 ohm, guess she just couldn't take it. I haven't opened it up yet to see how bad the damage is, nor have I hooked up another amp yet to make sure my Legacy's weren't damaged in the process.

Sure do wish Glenn would have time to get to my Adcom, I guess it is back to the twin Sons of Ampzilla.

Jim

In SS amps distortion approx doubles when you move from 8 ohms to 4 ohms. Also current requirements for a difficult load is increased. The faulty could be in the amp power supply. Maybe transformer or caps...?!

That's really a shame Jim. Do you have any idea what the DC offset was before the magic smoke escaped?

ack! thats a shame, hopefully any damage was limited to the amp.

I really think the problem was the extended time with a 3 ohm load, I had been using the power amp for over a year and a half under a 4 ohm load without any problem prior to the mishap.

Jim

ARGH!

Sorry to hear that, Jim.
What amp is it?
We've all done it thru one oversight or another,
or just the slip of an elbow.
Hope it's not as bad as it sounds.
dennis

Yamaha MX-800, it is going to need more than fuses.

Jim

The load was nominally 2.67 ohms, so no doubt that was the cause. If the DC offset was high it would have made the amp more likely to suffer a failure.

A healthy MX-800 can easily run a 1ohm amp, 2 ohm is its standard rating so I am sure there was something wrong with it already.

Output transistors "checked out" and probably fried emitter resistors hence magic smoke...Definitely going to take more than a fuse...