Operational amplifiers (commonly called op amps) are a ubiquitous building block for designing electronic circuits. Today, these devices are fabricated as small integrated circuits, but the concept ...

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 ...

Design analysis of the K2-W Vacuum Tube Op Amp’s design and operation reveals the mad science that created a commercial revolution in 1950s and 1960s analog computing. Op amps played a critical role ...

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 ...

Ex-movie theater projectionist Steve Guttenberg has also worked as a high-end audio salesman, and as a record producer. Steve reviewed audio products for CNET and worked as a freelance writer for ...

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 ...