Direct heated triode driver

 · a Direct Heating Triode blog devoted to quality audio equipment. Home; Listening room; Disclaimer; . 41MXP SE amplifier Part 2. Supply. Choke input is the way to go for most SE A1 amplifier with moderate current (below mA). Two good reasons: 1- .  · The driver stage uses a high-gain 12AX7/ECC83 dual triode that operates as a grounded cathode amplifier. The dual-triode grids are connected directly to the signal input. The input impedance is kΩ. Driver tubes are cathode biased with a kΩ resistor, and V plate voltage. The 27 is an indirectly heated triode that is less sensitive to microphonic reaction and it can be heated with AC from a Hammond M2 transformer. It is highly praised by vinylsavor and it is available in blue colored glass, which adds visual beauty to the preamplifier. It works very well with a 10K output transformer such as the Hammond C.

Allnic uses this direct heated triode 3AA tube to drive the B to its correct specifications via a choke plate inductor. The choke inductor (with a % permalloy core) has very low power loss and an infinitely high load impedance. A large handful of the absolute very first guitar amps in the s had DHT (direct heated triode) power tubes such as the 2A3 or B, and of course were married with Field Coil drivers. The guitar manufacturers didn't seem to evolve, but went with cheaper solutions as the hobby of guitar playing exploded. The peak filament AC is V peak (half of *). If you subtract this from the V bias you get V. Notice that in the table, the distortion more or less "linearly" increases with signal level (which, incidentally, is NOT normally characteristic of IM) until you get past 22V peak signal, then the hum modulation increases rather rapidly, reaching a maximum at about clip point (which is.

An additional 6SN7 tube functions as a current source and low impedance driver to the B output tube. There is a direct heated 5U4 NOS (USA) dual diode in. Real power drive: The driver tube is the 3AA (or equivalent). Allnic uses this direct heated triode 3AA tube to drive the B to its correct. The subject of appropriate driver tubes for direct-heated power triodes is quite esoteric to most consumers. Investigating it just cursorily presents.