I have a balanced amp that's uses 2 P and N-channel JFETs per board.
The amp uses 4 boards in total.
How should I match the transistors?
The amp uses 4 boards in total.
How should I match the transistors?
- Do I match them per part label? (Example: Q5 is a P-channel part so I need a quad match for this part)
- Do I match for all the JFETs on the board? (example: Q5/6 are P-channel parts while Q7/8 are N-channel ones. I need a quad match for these 4.)
Which is the squematic under question? Matching will vary acording device's task. It is not the same for series, parallel or bridged.
If the amp relies a lot on feedback then its probably only outputs that need matching.
How much they need matching depends on emitter/source resistors on output.
Larger resistors need less transistor matching.
Very small or no resistors needs much better transistor matching.
How much they need matching depends on emitter/source resistors on output.
Larger resistors need less transistor matching.
Very small or no resistors needs much better transistor matching.
as an example, how about one of Nelson Pass designs. I believe 1 or more design uses K389 and J74.
Thank you.
PS: if you want a more concrete example, how about amp camp amp?
