VOX and BIRCH-STOLEC - 1968 to 1973
Birch-Stolec is well known as the company that took Vox over in 1970, moving production from the factory at Erith (Kent) down to the Ponswood Industrial Estate, St Leonards-on-Sea (near Hastings, Sussex) at some point after March 1971. Vox under Birch-Stolec became "Vox Sound Limited".
The Birch Stolec Limited inspection stamp in a late Vox Supreme.
For a growing body of info, pics and material on Vox Sound Limited see this page.
The Back Story
Birch-Stolec, or rather "Stolec", began in the mid sixties as a specialist switch manufacturer, owned by George Stow. Home seems to have been St Leonards-on-Sea from early on. Besides "Stolec", George Stow had three other companies: "Stow Electronics", "Digitizer Techniques" and "Technical Encapsulations Limited". These last were liquidated in March 1970 to make way for "Birch-Stolec".
But "Stolec" (ie. not yet Birch-Stolec) had business with Vox - "Vox Sound Equipment Limited" as it was then - from 1968. "Twickenham Transformers", which Stow Electronics had taken over in 1967, made the transformers for the VSEL solid state amps.
The driver transformers are marked "TT", and the main power transformers, always with an unpainted metal top in the VSEL period, are sometimes marked too.
Click as ever for larger images. Above, details from a "Vox Sound Equipment Limited" Defiant and Supreme, both with transformers made by "Twickenham Transformers".
In addition, there is report that Stolec / Stow Electronics supplied Vox in 1969 with switches - switches being Stolec's speciality. The switch side of the business was bought out in 1973, coinciding with the end of production of the existing Vox line at St Leonard's.
At any rate, the upshot is that George Stow knew the business well before he bought it. Effectively the Birch-Stolec group acquired a company that it was really already involved with, doubtless seeing some sort of profit, and future, in taking the ailing (and possibly almost defunct) VSEL on in early 1970.
"Twickenham Transformers" probably later became "Lemark" - Lemark's premises in Haywards Heath, Sussex, had formerly been owned by "Twickenham".
Some notes on Twickenham Transformers
Up to 1967: based at 301 Richmond Road, Twickenham - so the name.
1967: taken over by "Stow Electronics". Based at Bridge Road, Haywards Heath, Sussex. Signalled in The Electrical Times, volume 154, and in other contemporary notices (click on the Electrical Times link to go to Google Books).
From 1968/1969: move to the Ponswood Industrial Estate, St Leonards-on-Sea, near the Stolec factory.
Probably 1971: Lemark Transformers active in the Haywards Heath premises making units for "Vox Sound Limited". Lemark may well simply be "Twickenham" rebranded.
Above, the Lemark transformer in a "Vox Sound Limited" Foundation Bass from end of days (1972). Lemark presumably took over the Twickenham Transformers works at Haywards Heath - which is how Birch Stolec will have come to own and employ it.