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Vortexion produced this Dance Band PA Equipment during the mid 1940s

Vortexion CP20A

Vortexion portable mains/battery amplifier, the CP20A from the early 1950s

Vortexion Super 50

Early version of the Vortexion "Wimbledon" amplifer also issued as the "Super 50". This amplifier, like much of the other Vortexion equipment was in production for many years.




A short history

Vortexion Ltd of Wimbledon was a notable British manufacturer of high quality public address amplifiers, mixers and much later, tape recorders. Having been formed in October 1936 by two brothers, Sidney and Edward Brown. Vortexion was born out of a small shop trading under the name of Brown and Salter, who had been a supplier of components, later specialising in transformers. Nothing further is known about Salter who does not appear to have featured in the later history of the firm or in the formation of Vortexion Ltd.

The firm originally traded from 182 The Broadway, Wimbledon and expanded a little further along the road into premises at 257-263 The Broadway. With the unexpected death of Edward Brown in the February of 1942, Sidney’s wife, Dorothy assumed the position of a director.  Although never a large concern, at their peak in the 1950s, Vortexion products sold in relatively large numbers as evidenced by the survival rate of some of this equipment today.

By 1937 their first portable amplifier was introduced under the Vortexion brand name, capable of operating from the mains, or off a 12V battery, drawing some 6 amps. The CP20 could deliver a 15W output.

Vortexion CP20

The Vortexion CP20 Amplifier as seen in a slightly later Wireless World advert from 1939

With the outbreak of war, the firm found themselves under the direction of the UK Government for war work, and during this time the CP20 had been joined by an amplifier chassis featuring a pair of 6L6s in the output stage. Vortexion claimed that many hundreds of these were in use by the ARP and government. The claimed output from this amplifier was 50W. 

Post war they produced a recording amplifier type AD47 for disc recording purposes and a Magnetophon recording and replay amplifier in the summer of 1947 specifically to drive the German originated magnetic tape recorder deck of the same name. This development makes them an early, if not indirect entrant into the tape recording field as the UK did not see magnetic recording commercially introduced until a little later with the professional EMI BTR1.  The domestic markets would have to wait until 1948/9 before the emergence of a complete home tape recorder such as those produced by Ferrograph and the Thermionic Products “Soundmirror”. Vortexion did not produce their own self contained recorder for these markets until early 1953 a subject which will be returned to shortly.

In early 1949, the firm announced a stereophonic amplifier using as the output valve in each channel, a single PX4. Unfortunately, nothing further is known about this development although the equipment continued to be advertised in one form or another throughout the early 1950s.