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Arfa Daily Arfa Daily is offline
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Default amplifier loss of signal strength


"Eeyore" wrote in message
...


Arfa Daily wrote:

"Eeyore" wrote
ll wrote:

I recently installed a transformer (12VAC, 2Amp) in a musical
instrument amplifier (rated at 10 Watts RMS), and when I test it with
a variety of input sources (guitars, keyboards, different cables), for
about 30 seconds, the amplifier produces a nice healthy volume level,
and then, consistently, the volume just drops about 50%. For some
reason, this problem sounds like it might be heat-related. Has anyone
else experienced this?

Are you by any chance sine wave testing it for those 30 seconds ?



I took it he wasn't, as he says that "when I test it with a variety of
input
*sources* ... " and then specifically mentions guitars and keyboards.


I was a bit dozy at the time.

I've seen that effect though.

Graham


Likewise. I often deliberately test group amps with a 400Hz tone for a few
minutes, just to get the output stages thoroughly thrashed up to
temperature.

Arfa