What are your thoughts for the attached plan?
I drew a simple pcb for testing purposes. I plan to do live tests soon.
I drew a simple pcb for testing purposes. I plan to do live tests soon.
Attachments
Last edited:
If you want to avoid unity gain feedback stability issues, you might try the kulish corrector for the output: https://www.diyaudio.com/forums/solid-state/74861-single-darlington-line-preamp-3.html#post856982
A general remark: using HV transistors like the MJE's when they aren't actually needed is counter-productive.
Everything else being equal, this type of transistor is slower, has larger capacitances, lower gain, higher parasitic resistances, etc.
They are lots of low-voltage alternatives in a similar case
Everything else being equal, this type of transistor is slower, has larger capacitances, lower gain, higher parasitic resistances, etc.
They are lots of low-voltage alternatives in a similar case
indeed , as it hints to low noise, bc327-40, 337-40 might be a better choice for MJE pair transistors.
Fairchild or ON bd 140-139 have the highest hFE but not good enough...bC 327/337-40 should be much better although i'd go also with 2sc2240/2sa970 pr 2sc1815-2sa1015 as they are ow noise too, have enough current and high hFE.