Custom Fabrication

Bogen DB20 Equalizer Circuit circa 1953

From the October 1953 edition of RADIO ELECTRONICS comes this report on an exceptionally powerful EQ circuit as-found in the…

3 years ago

SuperHugh: studio instrument preamp

I tried to imagine the sort of custom instrument preamp that a top session player might have brought to a…

4 years ago

Altec 436C style compressor build #2

I've serviced and modified many Altec 43X-series compressors over the years, but I think this may be only the 2nd…

4 years ago

Classic RCA riaa phono preamp / module-style

I've been developing an all-tube rotary-knob DJ console for the soundsystem at Berlinetta Brewing. One idea I decided to experiment…

4 years ago

Fairchild 663 Optical Compressor circa 1965

I was recently given this circa 1965 Fairchild model 663 optical compressor module. This unit was sold as part of…

4 years ago

“Detroit Boxes”: Motown-style transformer DIs

Detroit Box #001 featuring UTC Ouncer Transformer and O-17 magnetic shield Last year I found myself with an excess of…

4 years ago

Altec 1588C Stand-alone Mic Preamp

This is my first post using this intensely frustrating new Wordpress "Blocks" authoring structure so it will brief/awkwardly formatted. Why…

5 years ago

Western Electric 43A Homage Amplifier

The piece you see above is my homage to the Western Electric 43A.  The 43A, as far as I can…

5 years ago

New Mic Preamp “The Sienna”

Shown above is a pair of Preservation Sound "Sienna" model preamps.  These are the first designs to wear the 'Preservation…

9 years ago

The Olmsted AC Custom Microphone Preamp

The Akai and Roberts reel-to-reels have circuitry that is largely derivative of the American Ampex machines of the same period,…

9 years ago