Lemark Transformers (formerly Twickenham Transformers)
Detail from a picture of one of the assembly rooms in the Burndept / Vox Works at Erith, unfortunately NOT June 1967 as sometimes stated. It was taken in June 1969 - note the unpainted shrouds of the tranformers. In 1967 shrouds were black.
In early 1969, "Vox Sound Equipment Limited", still relatively new at that time, made the decision to contract out the making of the tranformers for its solid state range to "Twickenham Transformers", based in Hayward's Heath. Cost was the principal driving force for the change. Shrouds were bare metal rather than black.
Twickenham had been in the business since the early 1960s and was reasonably well known. In 1967 it had become a member of the "Stow Electronics" (Stolec) group of companies managed by George Stow. Twickenham, however, was not owned by Stow.
The link with Stow was important though, for when "Vox Sound Equipment Limited" ran into trouble in late 1969, it was Stow who played a key role, along with Michael Birch of "Birch Electronics", in saving Vox. Financial backing was found, and in early 1970 the company became "Vox Sound Limited". A few months later (in March 1970) Stow liquidated the four companies under his direct control - "Stow Electronics", "Startronic Limited", "Digitizer Techniques" and "Technical Encapsulations Limited" - to make way for the new "Birch-Stolec" group. "Vox Sound Limited" naturally became a member.
A few months later again - in the summer of 1970 - "Twickenham Transformers" became "Lemark Transformers", the Haywards Heath address remaining the same. Stow, who became managing director of VSL in early 1971 (see this page), maintained close links.
In terms of the supply of transformers to Vox, little except the labels on the units changed. Lemark retained the "Twickenham Transformers" model numbers:
Click as ever for larger images. Above, details of the mains transformer of a "Vox Sound Equipment Limited" Defiant - serial number 2032, made in early 1969.
The driver transformer - TT3944 - of a "Vox Sound Equipment Limited" Supreme.
Notes on the Twickenham part numbers adopted by Lemark:
Driver transformer: part no. TT3944.
30W mains transformer(Conqueror and Dynamic Bass): part no. TT3945.
50W mains transformer (Defiant and Foundation Bass): part no. TT3946.
100W mains transformer (Supreme and Super Foundation Bass): part no. TT3947.
Reverb driver transformer: part no. TT4070.
The reverb driver transformer of a Vox PAR100SS
The mains and output transformers used in the various versions of the PA50SS, PA100SS and Midas amplifiers were NOT made by Twickenham or Lemark, however. Part numbers are ZD231 and ZD232.
Open frame mains transformer in a Vox PAR100SS - part no. ZD231, maker at present unknown.
General notes on Twickenham Transformers and Lemark
Above, the Lemark transformer in a "Vox Sound Limited" Foundation Bass from end of days (1972). Lemark naturally gave the old Twickenham Transformers address at Haywards Heath.
Stow Electronics was effectively the centrepiece of the Stow Group, which was known as "Stolec" from 1967/1968. The other satellite companies were Startronic Ltd, Technical Encapsulations Ltd, and Digitizer Techniques.
(ref. "Electronic Components" magazine, no. 8, 1967; "London Gazette", 18th Nov. 1969; "Instrument Practice" magazine, no. 22, 1968).
The main business of the Stow Group was the manufacture of electronic switches.
"Twickenham Transformers" had come to be part of the Group by 1968, though the company was not at that time owned by Stow. Twickenham was based in Haywards Heath, Sussex.
(ref. "Electrical Times", no. 154, 1968; "Instrument Practice" magazine, no. 22, 1968).
Twickenham Transformers became Lemark Electronics in the summer of 1970. "Lemark" was named after Mark Dennett, son of director Gerald, and Lesley Jay daughter of Eric Jay who were also previously directors of Twickenham.
(Information from Chris Burtenshaw, who worked at Twickenham and Lemark from 1968 to 1984.)
The main Stow Group (Stolec) factory, new in 1967, was on the Ponswood Industrial Estate, Windmill Road, Hastings/St Leonard's on Sea, Sussex.
(ref. "Electrical Times" magazine, no.152, 1967).
It was this factory, under the wing of the "Birch-Stolec" Group from mid 1970, that took on the manufacturing of Vox equipment in mid 1971.
A huge thanks to Chris Burtenshaw, who worked at Twickenham Transformers, then Lemark Electronics, from 1968-1984, for key info.
A driver transformer from a "Vox Sound Limited" PA amplifier. These were also used in the guitar and bass amplifiers. As the sticker notes, the transformer was manufactured by Lemark Electronics, part number TT (Twickenham Transformers) 3944. The part codes of other transformers - all with TT numbers - will be listed soon.