Valve Regulated 300B

Power supply 1: 6080 and ecc83 as shunt regulator powering output stage

Power supply 2: Low noise solid state regulator power driver stage

Driver stage using two stages of 5687

211 A2 Amp

Circuit is 6sn7 voltage gain, the el84 cathode follower direct to 211 grid, in a similar fashion to Ongaku. The A2 driver is capable of sending the grid at least 40v positive, so peak power is just above 30w.

Fully Balanced Valve Preamplifier Bp1

Transformer coupled (Sowter), front and back, balanced gain stage, valve rectified, choke regulated power supply.   This design was started when I was asked for the "Best preamp you can make" So this is it. There are some test results available, but the real...

D3a Driven 2a3

The d3a is a great little high gm pentode to strap as a triode for use driving smaller DHT's.   Its not got enough grunt for a 300b. But it sounds wonderfull driving 2a3 or 45 (and if I could afford them the British output DHT's).   Valve rectifier and choke...