If you’ve ever wondered why something like a radio or a TV could command a hefty fraction of a family’s yearly income back in the day, a likely culprit is the collection of power transformers needed ...

The GA-10 is an audiophile-grade headphone amplifier that features the SEPP (single-ended push-pull) circuit with eight vacuum tubes, a linear transformer, and direct tube output. The vacuum tubes ...

This one is a superior class AB push-pull configuration tube amplifier project delivering 80 Watt RMS per channel. Four 6550 high power tetrode vacuum tubes in triode mode and class AB2 push-pull ...

Having built a number of vacuum tube output transformer-less (OTL) amplifiers in recent years, it seemed as though it might be a good idea to try combining older with newer technology and using both ...