I purchased one of these amps about two years ago. I expected it to require
50 to 60 watts of drive for full output but it only took half that. I was
worried about screwing up and hitting it with 100 watts from the K3 and
blowing the final transistor. I knew there was a pad on the input and I
figured it would be fairly simple to increase the attenuation 2 db or so.
I pulled the covers off the amp and discovered that there were 2 pads on
the input! The first was TO-220 style resistors mounted to a chassis rail
and the second was conventional wire-wound resistors mounted on the PA
circuit board. Replacing the TO-220 resistors looked like it would involve
quite a bit of disassembly and probably would void the warranty. Tack soldering
some resistors on the second pad to increase the attenuation would be much
easier and could be easily removed if it had to go back for service. Problem
solved, right? Nope. I discovered that the amp senses drive power after the
first pad. This meant the amp kept tripping off with overdrive warnings! I
contacted the factory to see if there was an adjustment I could make and was
told it would have to come back for "realignment"!
I now have a KPA1500!
73, Roger
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