• The swap meet forum is for private non-commercial transactions. Only unmoderated members can post here.

    diyAudio provides this forum for the convenience of our members, but makes no warranty nor assumes any responsibility. We do not vet any members. Use of this facility is at your own risk. Customers can post any issues in those threads as long as it is done in a civil manner. All diyAudio rules about conduct apply and will be enforced.

For Sale XA252 PoP R1

Things you have for sale.
well like you said, you got to a turning point with the power supply for you Blowtorch preamp because of not having enough voltage to drop across the ccs of the shunt regs that you want.
With the actual trafo a good but expensive solution is a lt3081 ccs and ZM’s gg error amp probably followed by some bjt cap multipliers if you want 2 stage regulation.
Some voltage can be gained also with active rectifiers.
Best would be another trafo with higher rails. The money you spend on the active bridges and the lt3081 brings you close to the price of a new trafo with the needed rail voltages.
Beside this with a trafo that has bigger rail voltages you can account for 10% mains variations.

Going with the higher rail trafo enables you to use the floating ccs in the gg but with some tweaking for a bit more psrr.

If you have some time one day we can speak on whatsapp and decide exactly what to do. It doesn’t take long to draw those aluminum pcbs and to populate them.
 
No problem and thanks for the nice words.

Your bt does pretty well already regarding noise.
noise.jpg


But if needed it can do even better like here
noise nosig 50khz.jpg
 
  • Like
Reactions: geoturbo