Did you ever get the issue resolved? Doesn't sound good in any case from what you describe. These amps naturally run very hot as I own one and know from personal experience. Considering the age of the amp it should have been completely recapped and all the output devices removed and remounted to the heat sinks using new thermal insulators as the old ones dry up and no longer properly transfer heat to the heat sinks. If none of this has ever been done then most likely what has happened is some of the output devices have shorted and taken emitter resistors out with them. Not a pretty picture as far as failures are concerned as I have seen similar failure scenarios literally burn holes in the circuit boards when this happens. And to add insult to injury, the original (Krell factory selected and matched) Motorola output devices have not been produced for nearly 20 years. Fortunately though for me, I rebuilt my KSA-150 before the time-bomb exploded and it is now good for another 25 years of service and of course still sounds fantastic. Where does your amp reside at this point?
