[Ynze] has built an audio amplifier that looks and sounds great. His amplifier uses a National Instruments (now TI) LM3886 Overture series 68 Watt power amp ... they use no circuit board.

It’s a conventional tube amplifier circuit in which the triode is a preamplifier for the pentode power output stage. The pentode is running in class A mode, and the high impedance of its output ...

TEAC announces its new HA-507, a Reference 500 Series pure analog headphone amplifier/preamplifier that incorporates TEAC's ...

Teased in prototype form at May’s High End audio show in Munich, the reimagined Quad 33 preamplifier and Quad 303 stereo power amplifiers ... transistor amplifier designs. This circuit layout ...