A single ended 211/VT4C vacuum tube Class A amplifier

After two years of researches and pilgrimages in various electronic fairs, I have succeed in finishing a project I have dreamed of for many years: a single ended with a 211 in double mono and 4 chassis. The care into realization was very accurate, rather maniacal. The connections (reduced to the minimum way) amongst the various components are executed with a military cable, silver plate copper, Teflon isolated, coming from a russian radar connector. The sole electrolytic capacitors are set into the 211supply filament, the rest are paper&oil. The feeder section of the 211 anodic voltage is formed by a third order pi filter, with capacitive input and 36 capacitors 10µF-1500V for both channels.

the first proto

An experimentation phase, but with 3 mm aluminium box, the side and wooden bands created later from a cherry tree

The base is MDF, containing into it (disposed on two floors) the paper&oil capacitors and the filter inductors, linked with full copper by 2.5 mm, for the power supply section (weight: 40 Kg)

The base and the left channel

side view

rear view 

Amplifier Construction Phase