Valve Regulated 300B

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   Interstage coupled to 300b output stage   Amorphous core output...
300b/GM70 Monoblocks

300b/GM70 Monoblocks

Circuit is a C3g Pentode voltage amplifier with VR tube screen regulator, then 300b driver to 1:1 amorphous interstage to GM70 grid. Output TX 7k amorphous. Driver and 300b supply, series regulator using 6080, ecl82 and 0d3 (Steve bench inspired). TJ-Meshplate 300b,...
211 A2 Amp

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.   All transformers by Sowter Transformers   211 DC heated...

Moving Coil Direct Input Valve Phono Stage

Valve phono stage using a JFET/ECC88 cascode to provide the gain and low noise of a solid state stage without the sonic cost of silicon and all the overload and sound advantages of valve stages. SPECIFICATIONS Overall gain 62dB at 1kHz Overload at 42v RMS output (40mv...
Fully Balanced Valve Preamplifier Bp1

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...
D3a Driven 2a3

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...