Power supply for headphone tube amp gives me 10-12V lower voltage comparing to the schematic (my measurements are in red for amp under load). Current under load is about 70 mA.
Using simple formula : 150V * 1.414 – 2V = 210V also gives approx voltage shown in the schematic.
I even tried to do simple simulation by using www.partsim.com, and it also gives about 170V for B+ and about 210V on the first filter capacitor.
I don't know what is wrong. I've triple checked all diodes, capacitors and resistors. They are all fine, and are connected correctly. I am still missing 10-12V.
Edit : transformer data
Best Answer
I will suggest an RLC filter than will only lose a couple volts. KVL indicates too much loss in DC for 80 dB 100Hz ripple attenuation. If your amp has some PSRR in the preamp you may compute that or measure it and reduce all R’s to 2.2 Ohms for now. When you come back with specs for DC drop and AC ripple, then a better sol’n is possible like an LDO or active filter.