Active current source or power resistor?

[woody]

I just built a small SOZ and while I am more than pleased with it
I would like to replace the source resistors with an active current
source so I don't need a ballenced input. Would a fet as a active current source be noiser than a 50 watt Dale chassis mount resistor in this aplication.


Thanks,

Woody

 

[Nelson Pass]

Making me trundle all the way over here from the Pass
forum, where this belongs, huh?

The current source biasing the Mosfets from the negative
rail is a superior technique, and was omitted from the
original article only due to its added complexity.

If you place a nice filter cap across whatever voltage
source is biasing the current source Mosfet (if you choose
to use a Mosfet ) then it will be plenty quiet.

🙂

 

[woody]

Thanks for the advice. I have changed to a mosfet current source
and like the results. The Radio Shack 8 ohm resistors that I had
as source resistors may have been adding a little noise!

Thanks,


Woody