[Mr Carlson] serves up another vintage offering, this time in the form of a tube op amp. The K2-W model he acquired enjoyed popularity when it was released as one of the first modular general purp ...

There’s a mystique in audiophile circles about tube amplifiers ... with the 40 V DC power coming from a DC-to-DC converter module. These amplifiers could be found back in the day in some ...

An audio amplifier that uses both tubes and transistors. The tube circuits drive the MOSFET transistors at the output stage because transistors can generate more power with less heat and ...