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Vortexion 400

CSI Vortexion Series 400induction Loop Amplifier first produced during the 1980s




CSI Vortexion Advert






A short history - 3

With the death of Sidney Brown in early 1972, the firm was subsequently sold to Clarke and Smith The changes in ownership were finalised in February 1973. Dorothy Brown remained a director on the board of CSI-Vortexion well into the late 1970s.

The new subsidiary remained largely autonomous until the January of 1974 when the entire production was moved to Wallington, although adverts appearing in the trade press were still showing the old Wimbledon address as late as July 1975. The original Vortexion factory on the Broadway, Wimbledon was finally disposed of in early 1976.


Vortexion CBL7T

The Rare CBL7T recorder dating from 1968/9. Rarer still, in mono as seen here. It was not thought any of these were sold. Clearly they were. This example turned up on a well known internet auction site in 2008.

The amplifier range continued to be made alongside the Clarke and Smith schools equipment, with development work and production already in progress on the CSI Vortexion System 2000 and an early announcement in the Wireless World of July 1975 proclaimed that the new amplifier “combined the aesthetics of design in the domestic field with the near flexibility of a modular system”.

This range was joined in the summer of 1979 by the VTN30 a 3 channel 30w amplifier, and later the VTN5a, an early induction loop amplifier. The final designs introduced were the Series 3000 during the 1980s with the final development appearing as the Series 4000, these were to include induction loop amplifiers such as the model 469, and a return to the battery powered amplifier in the 455 50 watt mixer amplifier that harked back to the CP50. With the demise of Clarke and Smith the brand name was sold off to Hagger Electronics of Letchworth, Hertfordshire who discontinued all but the induction loop amplifier range. This legendary brand name still survives today (just) in this specialised market.

If you worked for Vortexion or have any stories or pictures you would like to share, I would love to here from you as there is very little left on this highly regarded British firm.