Just a short (late) reply to tell everyone that the transfo used in most MP4 is running quite hot after a an hour or more of use. It is the result of Korg putting a 1.2 amp tranfo in a synth that consumes... 1.2 amps! So that part is working in the proximity of its maximum tolerance, and thus dissipates about 30 watts of heat. But that transfo is of high quality and should be able to handle that kind of heat easily. So I wouldn't worry about that. But no part is infallible and it could still fail.

Alain.

--- In korg_mono-poly@yahoogroups.com , "plus_321" <plus_321@...> wrote:
>
> Hello.
>
> Just a few moments ago I was playing some music and all of a sudden my mono/poly stopped working. I tried to flip the switch and nothing happens; no lights or sound. (I didn't see or smell smoke)
>
> I opened it up and the fuses are all fine, but the transformer was so hot that I couldn't keep my finger on it for more than a moment (even now, 15 minutes later it is still very warm).
> I used the service manual and checked on board 356 for voltages and none of them registered(5, 15, or -15).
>
> I'm not sure what to do now. I'm guessing the transformer died, but how can I know for sure What would cause the transformer to just go out like that If it is the transformer, does anyone here have a spare or know where to find one
>
> Thanks,
> Chase
>