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 ...

The circuit was designed to create a power amplifier circuit that will utilize E80CC and EL34 vacuum tubes for better results while providing 35 Watts of power. E80CC – a special quality double triode ...

It was a cold January Saturday night in Chicago and we had big plans. Buddy Guy’s Legends bar was packed. We setup directly under one of the PA speakers less than 15′ from the stage. Time to celebrate ...

A conventional tube amplifier has a circuit whose fundamentals were well in place around a hundred years ago, so there are few surprises to be found in building one today. Nevertheless, building one ...