Jennings Electronic Industries AC15 / V15
Spring 1972 - 1974
Illustration from the JEI catalogue of 1973 - the new model name (V15), livery and logo.
Introduced in time for the Frankfurt Music Fair (Musikmesse) of March 1972, the AC15 was Jennings's second foray into the valve market - the first being the AC40, on which see this page.
Notice from "Beat Instrumental" magazine, April 1972 - the introduction of the AC15 a surprise item at the Frankfurt Fair - price: £68.
From 1968 to mid 1971 JEI amps had solely been solid state. The move to valve was clearly driven by the market - valve was king. By the time of the Russell Hotel Trade Fair in August 1973, the AC15 had become the V15, retail price - £50.
Detail from the pricelist accompanying the new JEI catalogue of autumn 1973.
On the left, JEI prices in January 1974; on the right December.
Assembly of the chassis was contracted out to Triumph Electronics in Purley, which had worked for Tom in JMI days (from 1960 through to 1967). It is not known at present who produced the cabinets - possibly Gla-Rev or Heathpoint Timber of Thundersley in Essex.
Below, a detail of the circuit board of a JEI AC15 from late 1972 / early 1973. Note the printed legend: "TRIUMPH ELECTRONICS / PURLEY SURREY" followed by the Triumph mongram.
Trace side of the circuit board of a JEI AC15.
The JEI B50, O50, B100, O100, and the public address amplifiers, were also designed / manufactured by Triumph - see the entry for 26th November on this page.
Quite how Triumph's work for JEI fitted in with that of APT Electronic Industries (of Ascot and Byfleet) is not fully clear at present. It may be that APT, which came into the picture in the summer of 1969, took over production of designs originally developed by Triumph - see this page (report published in July '69). Close inspection of the trace-side of other circuit boards will probably reveal more.
Just to add that the boards of the B50, O50, B100, O100, and PA amps, have component numbers printed on their upper face. Boards of other amps - the J40, J100, J200, AC15, AC30 - tend not to.
The serial number sequence evidently began at 3000. 3093 is the highest currently known for the amp as an AC15, which may be close to the end of the first run. The V15 is likely to have continuedin sequence where the AC15 left off. No example so far of a "V15" has come to light yet though. The amp appears to have sold well in Europe. At any rate, greater numbers of AC15s survive there than in the UK.
Serial number 3022
NEW
Serial number 3086 - currently in Austria
Cabinet restored by the owner. The hardboard baseplate is new. Pots replaced some time ago. The black Callender capacitors have mid 1969 date codes. Thanks to Joe for the pictures.
Serial number unknown
The electronics built lightly on a printed circuit board, the controls (potentiometers) soldered directly on. Not all that robust, but this one survived.
.No circuit diagram has come to light so far for this amp. Its general appearance, the split level top in particular, is similar to a number of other small valve amps built by Rosetti and Triumph in the mid 1960s. It also resembles - a frivolous analogy - certain 1970s washing machines.
A Johnson 15 watter made by Triumph Electronics in the late 60s.
A Rosetti 15 watter made c. 1960.