At the extreme budget end of tube audio lie single-tube amplifiers usually using very cheap small-signal pentodes. They’ve appeared here before in various guises, and a fitting addition to those ...

If you ever wanted to build your own tube amplifier but you were intimidated by working with high voltages, [Marcel]’s low-voltage tube amp design might spark your interest. The design operates ...

The output transformers are the same ultralinear design ... shows how 40 years of electronic development can influence a design, even though both are tube amps! The Series II was designed in the early ...

The Dynaco ST-70 was the company’s first stereo amplifier. It utilized four EL34 output tubes, one GZ34/5AR4 rectifier tube, ...

Heart, a company owned by hi-fi dealer Rik Stoet, are a small Dutch manufacturer of tube amplifiers and of output transformers for said amps. Before you start making up jokes about the name, they ...