Re: filament starvation and noise? (long)


"Harrison Ford Prefect" <meo@xxxxxxx> wrote in message
news:13rne3p5oa8ks78@xxxxxxxxxxxxxxxxxxxxx
Phil S. wrote:
...
One side effect of what I did was to knock down filament voltage to
around 5.9-6.0 (depends on the day/time). The question is whether the
filaments are starved and is this a possible source of noise (hiss)?

Nope.

I have no ieda what the effect of really low filament voltage
would be on hiss, but I do know that published specs for every
tube in this class I ever looked at was +/-10% on filament
voltage. So the nominal voltage is 5.7 to 6.9. I've seen amps
running a little lower and a little higher with no noticeable,
ill effects.

Hi Miles:
Thanks for getting directly to the point. I thought this was the case, but
it doesn't hurt to ask.
Phil


.

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