Some time back I built a 71a preamp with 100 year old Cunningham tubes. This 01a amp is similar but these tubes have more gain. Once more Cunningham tubes. Regulated DC of course on the heaters and a resistor divider to balance the voltage further.
Sprague orange drops for output caps and remote control Alps Blue velvet pot. Fine silver plated copper wire for hookup and mostly metal film caps. Remote PS with double Pi filter for HT. 300uf of 400V filter caps. Had some hum issues but by reducing the gain managed to get this right down. Love the colour - Iron Stone - and the look. Excellent to listen to.
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