4SUTea is another Super Simple Single Stage (4S) Tube preamp that I have built. This one features single board construction with PS and amplifier together and no PCB. All housed in a Twinings timber Tea Box: Bitumanised aluminum foil controls enclosure resonance and Russian paper in oil caps...
If electret headphones are used, you won't one. Adding the bias voltage is no big deal, however, as the schematic below shows. Missing from the schematic is the 20M resistors that attach to the diaphragm. Actually, now that I look at the heater portion of the complete schematic, I could...
First it was the SRPP, then the Circlotron, and now the Ultrapath. The Ultrapath is not about PSRR or anything so banal, they will counter; it is a mega ingenious solution to boring tube amplifier sound. And it requires greater metaphysical acumen than JRB posses to grasp its transcendent ...