If I were to build only a preamp my assumption is I would not need an inductive filter. Capacitive with a resistor should be enough. Is that right? The circuit will be about 3 tubes.
silverfox.
Power Supply for Pre Amp Only circuit
Moderators: pompeiisneaks, Colossal
-
Stevem
- Posts: 5144
- Joined: Fri Jan 24, 2014 3:01 pm
- Location: 1/3rd the way out one of the arms of the Milkyway.
Re: Power Supply for Pre Amp Only circuit
Yes you can get away with out it, but in general you will likely need one more filtering node that does not power anything so that you will end up with the same low level of AC ripple voltage on the first gain stage as you have with a complete amp with a output stage.
Another way to go is to use much higher input B+ then you need and knock it down with a large value resistor into the power feed node who's filter is 80 to 100 uf.
Another way to go is to use much higher input B+ then you need and knock it down with a large value resistor into the power feed node who's filter is 80 to 100 uf.
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Re: Power Supply for Pre Amp Only circuit
It depends on the kind of preamp you are building, but I'd do it like that:
47uF 1k 47uF and then just add all the RC stages (cutoff around 1 Hz) for the other stages (series or parallel as you prefer).
47uF 1k 47uF and then just add all the RC stages (cutoff around 1 Hz) for the other stages (series or parallel as you prefer).