On Mar 28, 12:40 am, "Bill Noble" wrote:
you don't say what kind of noise - sometimes the fans pick up a lot of crud
The hum is louder than it has ever been before. The amp
is quiet when first turned on, but as it warms up, and
depending on the volume level of the program material, the
hum of the fans emerge. I assume this is because the fans
are thermostatically controlled. Oddly enough, the
frequency of the hum is constant as it gets louder. If
the fans' speed increased, I would expect the sound
to increase in frequency as well, but they sound the same
tone, which I'm guessing is 120 Hz. Anyway, on a recent
warm evening after playing a symphony, the fan sound
was irritatingly evident.
--
Charles Packer
http://cpacker.org/whatnews
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