Custom Fabrication

Vacuum-Tube Output Stage for Shure Level Loc

Many of my regular readers will be familiar with the Shure Level-Loc.  For those unfamiliar, the basics:  the Level-Loc is…

13 years ago

Audio Transformer As Signal Processor

Sometime in the past couple of years, Tape Op ran a short piece by Allen Farmelo titled "Using Transformers to…

13 years ago

Stereo Audio Power Amplifier (Home Use)

Above, a recently completed piece.  It is built on one of two identical NOS cabinets that I pulled from a…

13 years ago

The BRDCSTR

Above: The BRDCSTR, a two-stage vacuum-tube microphone preamp inspired by classic 1940s broadcast audio preamps.  Single-ended design with a 6SJ7…

13 years ago

The Old ’76

My latest microphone preamp design is completed and sounding very cool... The Old '76. The Old '76 is a novel…

13 years ago

A couple of recent guitar amplifier builds *Revised (2)*

Cassius #10; aka #10 in the the ongoing series of Fender Champ-derived guitar amps built into recycled 'found' vintage speaker…

13 years ago

Sound From A Glass Box

This design project began with the goal of crafting an entire amplifier that echoed the form of a vacuum tube…

13 years ago

Marantz 7 RIAA Phonograph Preamp

For my non-technical readers: a phono preamp is a device which does two basic things:  1) it equalizes the program…

13 years ago

Altec 438A – Modified for modern music production use

As we discussed in previous posts, the Altec 438A is an audio compressor designed in the late 1950s primarily for…

13 years ago

Leslie Rotating-Speaker Interface Unit – UPDATED

The Leslie Model 51 is a single-speed, large Leslie unit with 2 amps, a 15" woofer, a rotating horn, and…

13 years ago