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Re: Hum pot in DHT preamp ???

212.185.252.197

Hi!

> did you ever consider connecting the bias resistor to the positive > side... this will buy you some extra bias
> voltage, and allow for a slightly smaller resistor for the same

I'm not sure if I understand what you mean by this,
but with the filament bias approach this wouldn't work.
With filament bias, the filament itself is actually a
substantial part of the bias resistor.


> i assume since you are using it, you like the sonic results of > the bias resistor :-)

Im my 801 linestage the bias resistor is only 33 Ohms.
I still use the ultrapath connection. The B+ side of
the lineout transformer is returned to the - side of
the filament. So the AC signal actually bypasses the
bias resistor (at least from the midrange on upwards)

Thomas


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