From Wikipedia

(1922 – 6 November 2000) was an English luthier mainly known for his electric guitars. His customers included Tony Iommi and Geezer Butler of Black Sabbath, Brian May of Queen, Manny Charlton of Nazareth, Dave Hill and Jim Lea of Slade, Gerry Shephard of The Glitter Band, Roy Orbison and Nicky Panicci.

John Birch was born in West Bridgford, Nottinghamshire, United Kingdom in 1922. He became involved in guitar building as a Royal Air Force officer based in the South Pacific Islands in World War II. Returning to England at the end of the war his interest musically was in collecting Hawaiian Records.

In 1963 he met Basil and Pat Henriques of the “Waikiki Islanders” group, a Hawaiian group formed by Pat’s father Bill Cox and his brother Archie in 1937. Birch was, during the ’60s, living at 33 Innage Road Northfield and working as a field service engineer for Ampex VTRs.

After a series of experiments with a few joint designs Basil Henriques and Birch (using Henriques’ Fender 1000 pedal steel guitar as a testbed) came up with a new pickup design using multiple polepieces and a coil potted in baked epoxy resin. On subsequent BBC “Night Ride” broadcasts and later EMI Abbey Road recordings, the pickups on Basil’s guitar proved to be a revolutionary design in both sustain and fidelity. EMI were so impressed with the stereo sound of Basil’s guitar that they offered Basil and the Waikiki Islanders a 10-year contract on their Stereo Label “Studio Two Stereo”.

At Basil’s instigation, John quit his day job and started making pickups for the guitarists in the local Birmingham beat group scene. Much later on (in the late ’80s) John was again to use a pedal steel guitar as a testbed, this time for a MIDI pickup system.

Biography
After the war was over, he came back to Nottingham and started a business modifying existing guitars. Beginning in the 1960s, he mostly worked with Gibsons, an example of which is the white Gibson SG Junior Leslie West of Mountain gave to Tony Iommi (the guitar is currently owned by Greg Dorsett of Rock Stars Guitars). He eventually started building his own guitars. Later he moved his shop/factory to a large house at 106 New Road in Rubery, near Birmingham GB.

Birch started to advertise his parts, pickups, and guitar customization in a magazine called Beat International in the late 1960s. John Diggins saw one of these ads and showed one of his custom guitars to John Birch. Diggins was offered a job and became part of Birch’s workshop. Arthur Baker came in as a production manager, breaking down the various jobs around the shop to create an assembly-line-like process. Birch was mainly in charge of electronics and pickup making while Diggins mostly took care of woodworking. There were many other employees through the years, though the roles stayed largely the same.

The very first guitars that were made completely in shop were SG- or Les-Paul-shaped, featured 24-fret fingerboards, and a black or white finish. At first, the fingerboards were Brazilian rosewood, but eventually the expensive and rare Brazilian Rosewood was replaced with more plentiful and cheap maple fingerboards.

The majority of the shop’s guitars, like those of most small outfits meeting the demands of players during the British Invasion, were built quickly and on the cheap. John Diggins, however, was a master craftsman and always built top-notch instruments at the shop.