Daily Archives: 1st December 2014

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

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.

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.

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 power supply. James output transformers. CCS…

Moving Coil Valve Phono Stage With Valve Regulated Supply

Specifications Overall gain 43dB at 1kHz Frequency response within 0.1dB of RIAA from 20Hz to 20kHz. All filter components hand matched to within 0.1% tolerance. Active loaded output driver provides low impedance, low distortion output to preamp or integrated amp Single stage high accuracy EQ provides stable imaging and wide soundstage. No feedback used in…