I've been looking for a decent Hercules 444 amp to go with my Omni-C for
some time. I came across one that didn't work, and the imbalance
shutdown light was on.
The amp in question probably has one or more blown finals.
Ten-Tec used MRF428's in the final. Their service dept tells me
that original spec MRF428's are no longer available. They also
mentioned that replacement MRF428's made in the last few years
have higher gain (HFE) than the originals and will "take off"
and blow in a few moments if used. Apparently, no other subs are
suitable. Thus they consider the amp unrepairable.
Has anyone had experience with this?
I'd think that with a lot of trial and error, for someone with time
to "burn", negative feedback could be added to reduce final gain.
The problem would still be to balance both modules. The imbalance
protection circuit would immediately shutdown the amp if that wasn't
done. Obviously, Ten-Tec would not want to do this sort of
reengineering.
One of these days, I'd still like to get a 444.
Are there any owners out there who have gone through this?
73,
Doug/WA1TUT
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