The Power Supply The Power Supply Internal Construction Internal Construction

The Power Supply

The power supply is as much important as the circuit itself. It is the heart of any good planned amps. I used classical schematic of full-wave rectifier with Pi-filter (C-L-C). In my opinion tube rectification sounds better than silicon diodes one. Voltage drop across kenotron tube is not a problem, because single ended amp works in Class A and use the constant value of DC current.

For inductance coil I took Audio Note AN-160 choke with 10 Henry value. It looks solid and is bigger than Hammond models.

Filters input capacitor is very important for sound character of tube amp. I have changed film capacitor to paper-in-oil cap and was very surprised! This change brought the great improvement of the sound. I can describe it in two words: relief and gentle.

In power supply you can see hard to find (discontinued) japanese Elna Cerrafine 220uF 500V cap.


Level Five 2A3 Schematic