Vox AC30 website updates
October and November 2020
29th November
A grey panel chassis, integrated top boost, probably from an amp with a serial number in the 15000s. Transformers are Parmekos. The remains of a dome voltage selector are present. One of the capacitors in the power section has the date code "VF" = June 1964.
Also present are the original Mullard preamp valves and GZ34 rectifiier; two of the ECC83s have the date code "LE" = May 1964, a further ECC83 and the EC82 have "LF" = June 1964. Only the "L" (1964) of the GZ34's code is visible.
28th November
A side note on Woden transformers. Below, a couple of pictures of a British-made amplifier (manufacturer unknown), said to have been produced for the amplification of cine / film soundtracks. The Woden mains transformer (115v primary) has the date code "AU" = January 1963. Its shroud is of the same form as the transformers that Woden made for Vox in the autumn of 1964 - plain metal with stencilled details.
Transformers with plain shrouds will have been a less expensive option than enamelled. Woden supplied units with green enamelled tops to Vox from autumn 1962 to early 1964. From autumn 1964 through to spring 1968 Vox used Wodens with plain tops and a slightly simplified internal structure (for the output transformer).
Copper panel and style of lettering similar to Vox panels; but this is certainly not a Vox amplifier.
27th November (3)
Below, pictures of Super Twin amplifier section serial number 5596TB. Its Woden transformers have the date code "BZ" = February 1968, and the choke "CZ" = March 1968. The amp will have been among the last produced by JMI, which finally ceased trading in late Spring '68, having been in the hands of the "Official Receiver" since December 1967. Receivers oversaw the business of companies that were in dire financial straits. Trading could continue under supervision, but all expenditure had to be sanctioned.
Given the date of manufacture of the Wodens, serial number 5596 is likely to have been ready for sale in April or perhaps May 1968. Thanks to Ihor for mentioning the existence of the pics.
Chassis number 25139. JMI serial number plate. Top Boost controls in panel.
27th November (2)
A new page has been started on AC30 cabinet makers and cabinets - for the moment principally Twins. JMI's chief contractors were: P.A.Glock in Crayford, a mile or so away from the Dartford Works; Gla-Rev (Henry Glass) in Hainault (Essex); Heathpoint Timber in Thundersley (Essex), and Timber Techniques / Heslop & Co. in Rayleigh (Essex) - the Gladlyn Works. Heathpoint was just down the road from Heslop.
It is clear from surviving amps that there was a basic specification for AC30 cabinets to which all companies adhered (for the most part anyway). There is no such thing as a "thin-edged" or "thin-lip" AC30.
AC30 Twin serial number 6097.
27th November
Below, details from a black panel TV Front AC30/4 currently in Finland - registered here. Thanks to Valentin. Note the WIMA Tropydur caps in the preamp.
The date code on the Hunts cap is "IAY" = 19th week of 1960 (May).
Above the green TCC preamp filter cap, and the main power section cap.: date codes "RC" and "RJ" = March and September 1960 respectively.
26th November (2)
Alan Hope, guitarist in the band "Kerry Rapid and The Soultones", with a TV Front AC30, probably late 1960 / early 1961.
Picture from this page.
26th November
"Melody Maker" magazine, 30th April, 1966 - advert placed by "Pan Music" on Wardour Street. Two Vox 30 watt PA amplifiers, one with a set of column speakers, and among other things, a Vox AC30 Super Reverb Twin II (ie. with two 2x12" speaker cabinets) for £80 - perhaps an old one given the price. The retail price of an AC30 Super Reverb Twin II was normally £209 in early 1966.
Pan did good business selling Vox. At one point in 1965, it had around thirty AC30s in stock at discount prices, presumably the fruit of a deal struck with JMI.
"Melody Maker" magazine, 30th April, 1966.
Picking up from yesterday's entry, just to say that MC30 serial number plates will have had no designation of "voicing" - in other words no "N", "T", "TB" or "B" after the serial number.
25th November
Below, a detail from the Vox "Precision in Sound" newspaper format catalogue, late 1964 - the M.C.15 and M.C.30 public address amplifiers. 50 watt and 100 watt version were also available (the M.C.50 and M.C.100). All were cast as "multi-purpose" units - for groups, clubs, theatres, factories, and so on. General arrangement of the fascias was the same: four channels (three for microphone, one for music) each with its own volume control; general treble and bass controls to their right; and underneath, lower right, the ON / OFF switch. Metalclads were initially all valve (including rectification): two EL84s in the case of the M.C.15, four for the M.C.30, though whether these were run in cathode bias is unknown.
The PA ampliers did not have their own serial number plates and numerical sequence, however. M.C.50s were sent out into the world with standard AC50 plates, the model stamped as "AC50" not "MC50", and the serial number simply a member of the normal AC50 serial number sequence. Examples survive from 1965 through to 1968. A similar procedure is likely to have been adopted for M.C.30s and M.C.15s. It may be that some of the AC15 and AC30 serial number plates that come up for sale on their own from time to time actually belonged to PA amplifiers rather than guitar combos.
During the course of 1965, various changes followed - transistor preamps (as an option) came in, along with several formats of case (sloping fronts giving way to flat), and various permutations of speaker output sockets. Surviving M.C.50s from 1965 are solid state rectified - see this page.
Detail from the Vox "Precision in Sound" newspaper format catalogue, late 1964.
24th November
"Melody Maker" magazine, 2nd July, 1966 - advert for a 30 watt Vox PA amplifier and a pair of column speakers, presumably 4x10s. The amp is likely to have been an MC30/4 (MC = Metalclad), produced in at least two formats from 1964 to 1967. So far, no surviving example has come to light.
"Melody Maker" magazine, 2nd July, 1966.
22nd November
A note on the diamond-pattern "rexine" ("rexine" was the trade name) used on a large number of JMI amplifiers (though not all) from late 1957 / early 1958 through to Spring 1961. Below, a detail of a TV Front AC30/4 produced around May 1961:
Rexine was initially produced by ICI (Imperial Chemical Industries). In the late 1950s Wardle Storeys (British Xylonite) assumed production at its works in Manningtree, Essex. Wardle Storeys also made "vynide", a tougher more pliable form of covering. Black basketweave vinyl is "vynide".
Various types of patterned rexine were available, the patterns embossed on the material by special rollers, unfortunately destroyed when Wardle Storeys went out of business in 2005.
The question is how did JMI come to choose diamond pattern? The answer may be that the idea came from radios made by the KB company (Kolster-Brandes) which was based in Foot's Cray, a short step away from Dartford.
From the late 1950s, the KB Rhapsody Deluxe had been produced in the same two types of diamond-pattern rexine adopted by JMI - white, and off-white. Below, pictures of two examples:
Picture from the Radio Museum. A useful overview of the history of Kolster-Brandes can be found here.
Did Tom, Derek and Dick get the idea from a KB radio? More likely perhaps than KB's getting the idea from a Vox amp. All this of course is completely unprovable. The choice could equally well have been made independently from a sample / pattern book. But who knows. Thanks to Valentin for bringing the question of the radios to light.
Combo Organ Heaven is still the place to find out about organs - its findings have often been slipped without mention into other webpages.
20th November
It seemed best to set up a page on Allan Billington - now available here - some Jennings early history, along with examples of equipment (notably Vox) sold by him in the 1960s. A page on the varieties of early JMI amplifier - the work of Derek Underdown pre-Dick Denney - will be linked up shortly.
19th November
Currently on ebay.uk, the serial number plate of AC30 number 10356N with the shop plaque of Alan Billington. Billington was the first manager of the Jennings shop at 100 Charing Cross Road (from December 1950), leaving in 1956 to set up business for himself in Welling - see the entry for 30th July on this page.
14th November (2)
Sold on ebay some time ago - AC30 serial number 12563 (Super Twin amplifier section) serving as a PA amplifier with two LS40 speaker columns. A picture of an identical set was printed in an edition of "Banjo, Mandolin and Guitar" magazine in the mid 1960s - to follow.
14th November
Thanks to Andy, pictures of serial number 6893 from the first third of 1963. The amp was refurbished by JMI around mid 1964 - the Celestion blues have March 1964 date codes. At some point thereafter it was assigned by JMI to a Vox demonstrator, so may have been a demonstration amp from the outset.
10th November
Just to update yesterday's entry, batches of pots with the date code "EK" = May 1963, were evidently also supplied by Egen.
Detail of a pot on a chassis from mid 1963.
A new page - a sort of overview at present - has been started on the numbers stamped on chassis by Burndept, one of JMI's principal contractors, late 1962 to early 1968. Remember that these numbers do not provide a particularly useful guide to the date of an amp. They may get one to a year (if one is lucky), but other elements - component date codes and so on - are far more telling. Speakers generally have the latest codes so get one closest to the point at which an amp was ready for sale.
9th November (2)
Batches of components, late 1962 and 1963: in late 1962, one finds Woden transformers with date codes "HT", "JT" and "LT" = August, September and November 1962. In early 1963 a large batch arrived with the date code "AU" = January 1963. The next after that arrived in the autumn, date codes "HU and "JU" = August and September 1963.
One sees a similar pattern with potentiometers (which were made and supplied by Egen Electric Limited of Canvey Island): in late 1962, date codes "JJ" and LJ" = October and December 1962; then in early 1963, a large batch dated "AK" = January 1963. The next after than seems to have been "FK" = June 1963, but it is possible that there were consignments in between - in many amps the codes are not easy to see - so the picture must remain provisional for the time being.
9th November
Two more AC30 Twins with serial numbers in the 6000s registered here - 6534N and 6948N.
8th November (2)
A page gathering together material published by JMI in 1958, principally on the Vox AC2/30 - though much else is encompassed - is now available here. Further items will be added soon.
As the page grows it may be necessary to give sections pages of their own.
22nd March 1958. The two versions of the AC2/30 have been reduced in price by 8 guineas (from 62 and 70 guineas respectively). But in an advert placed in "Banjo, Mandolin and Guitar" magazine, May 1958, the prices are 62 and 70 guineas again.
8th November
Pictures of Super Twin serial number 2960 - grey panel - added here. Some later Super Twins and Super Twin Reverbs to come.
7th November (2)
FURTHER SUPER TWINS: Serial numbers 11575 and 2879 on this page. Serial numbers 3003, 3017 and 3134 added here. Some of the earliest amps on the Super Twin page, serial numbers 3000-6000, are likely to be late 1964, so the heading has been adjusted.
Serial number 3017 also exists as a "Super Reverb Twin" (with its early trolley) - here - so perhaps simply a mistake, human error in the time of hand stamped plates.
Super Reverb Twin serial number 11118 now registered here, the latest AC30 SRT to have emerged so far with a serial number in the standard Twin sequence. The plate is headed "AMPLIFIER" rather than "VOX AMPLIFIER" as some were for a short period in the first half of 1964.
7th November
A series of updates coming soon - Super Twins, further AC30s with serial numbers in the 9000s, and a new page on serial numbers in the 18000s.
30th October
Thanks to Sean, pictures of Super Twin amplifier section serial number 7167 N, from mid 1963. A previous owner used the amp in sessions with Joe Meek.
29th October
A black panel AC30/6 from late 1960, sold in Italy in 2014 - pictures here - and again relatively recently on Reverb. The speakers have date codes 16JE and 23JE = 16th and 23rd September 1960. Note however that the "VOX" label is heavily scratched. The Celestion label on the BO24, on other hand, is comparatively clean. The solder on the BO24 speaker terminals is not original. The pink and yellow speaker wiring is however.
25th October
Details of the JMI catalogue and pricelist printed for the Frankfurt Trade Fair - the "Musikmesse" - of March 1968 (the date of the catalogue). This was the last trade show of any sort that JMI attended. Soon after, the company ceased trading, to become "Vox Sound Equipment Limited" (VSEL) in the late summer of 1968.
The AC30 Top Boost. Six inputs, three channels with their own volume controls, two of the inputs for vibrato, operated by a footswitch. General tone control and dedicated treble and bass.
The two types of stand (in order) are swivel and fixed.
23rd October
The page on AC30s with serial numbers in the 17000s, late 1964 / early 1965, is now up. From 1965, speed of production dropped significantly. In 1964, around 8,000 AC30s were produced. From 1965-1968, only around 6,000.
22nd October (2)
The page on AC30s with serial numbers in the 17000s, late 1964 / early 1965, coming shortly.
22nd October
A couple of interesting things on Reverb at the moment. (i) a black panel AC30/4, probably from early 1961, original transformers in place. The amp is listed here. No serial number plate or relevant date codes visible on the components unfortunately.
Five of the six original circular ribbed black control knobs (with small inset pointers) survive. These are of the type illustrated in the JMI booklet of early 1961.
The AC30/6 panel illustrated in the JMI booklet, same type of knob as those on the AC30/4 above.
(ii) an AC30 Super Twin amplifier section, serial number 3134, late 1964 or early 1965, its tag still present - "VOX" in cursive - i.e. the earliest/first style of tag. Listed here.
20th October
A little more on Woden transformers. As it stands, the latest date codes on batches with green tops (the earliest type) appear to be "AV" = January 1964. The chokes accompanying these generally have "BV" = February 1964.
The new batches with plain metal tops came in later in the year, the earliest being "JV" = September 1964. Woden also made new batches of transformers for the AC80/100 at this time (amps with black control panels), along with a small run for the AC50.
So far no Woden AC30 transformer has turned up with a date code between February and September 1964. For the most part, Albions and Parmekos were used in this period.
The new batches of Woden AC30 output transformers (with plain metal shrouds) have a simplified internal and external construction. Externally there is only one red wire for the HT instead of a pair, and single wires for the secondaries (the output taps) instead of pairs. From a constructional standpoint, the new Wodens for the AC80/100 were exactly the same as their forerunners, however. Only the shrouds are different.
To date, the latest new-style Wodens for AC30s that have come to light are from November 1966 (serial numbers in the 22000s) - Woden date code "LX". Whether there are any with still later codes remains to be seen.
19th October
Serial number 6443B now added here. The latest observable element is the TCC preamp filter cap, date code "TM" = December 1962, so the chassis was assembled (by Westrex) early in 1963. What may be the Westrex inspection stamp survives by the underside of the output transformer. Thanks to Glen for the pictures.
One can make out "WEC" which is likely to be "Western Electric Company" (Westrex) followed by an "L" and a smudge, perhaps "Ltd".
18th October
Currently on ebay.de, serial number 22177, very little changed since it was made in early 1967. Visible date codes are - blue Erie/Hunts cathode bypass caps "UWY" = 10th week of 1966; Woden transformers and choke "JX", "KX" and "LX" = September, October and November 1966; and the red CCL 8uf capacitor "L6" = December 1966.
Note the red Lemco capacitors and the large parti-coloured Dubilliers at right.
16th October (2)
Picking up from the entry on Vox in Australia - below (15th Sept.) - an advert placed in the "Canberra Times", 29th June, 1964, by Donoghoe's Music Centre, Queanbeyan (nr Canberra).
Donoghoe's signalled the availability of Vox amplifiers on 15th June, but only as part of a general indication of what was in stock.
"Canberra Times", 29th June, 1964. The ad is a version of the one placed by Nicholson's earlier in the month in the "Sydney Morning Herald".
13th October (2)
Interesting how one thing leads to another. Below, Russ Sainty and Rhet Stoller (with guitar) at the California Ballroom, Dunstable, at some point in 1960. The California opened in March of that year and Sainty and Stoller's band the "Nu Notes" featured regularly.
In the background, two TV Front AC30s, the one with "ROY" on the front belonging to Roy Toft, rhythm guitarist of the group.
13th October
Tony Howard and the Dictators, winners of the Bournemouth "Big Beat" competition in February 1964. Picture from this page. The amp looks very much like an Extended Frequency AC30, just released at that point. Note that an Extended Frequency AC30 was illustrated in the Rhet Stoller competition of much the same date.
Rhet Stoller competition (organised by Larry Macari). Detail from "Record Mirror" magazine, 14th May, 1964.
9th October
Below, the advert for a number of Vox amplifiers in "The Shadows Modern Electric Guitar Tutor" from early 1963. The AC10 Super Reverb Twin was new in February '63 - see this page. The prices correspond with those given in "Melody Maker" magazine in early February too.
The "Modern Electric Guitar Tutor" also contains some excellent material on the Vox Phantom guitar.
7th October
"Melody Maker", 21st January, 1956 - a fiendish thingy. To judge by the description, a preamp (with octal socket input and output) designed to be plugged into the power section of an electronic keyboard - ie. an organ or Univox with built-in speaker. The keyboard could be plugged back in via the octal socket on the fascia. Doubtless a Derek Underdown design.
"Melody Maker" magazine, 21st January, 1956. Note the Jennings badge on top of the unit. Presumably a set of instructions was provided.
5th October
The page on serial numbers in the 16000s is now up. Some of these amps are likely to have been made around the time that the first big American order came in in late August 1964.
1st October (2)
Just to signal the presence on Reverb of a pre-LOC black panel AC30/6 from late 1960 - the Celestion speakers (one BO24 and one CT3757?) have date codes "16JE" and "23JE" = 16th and 23rd of September 1960. No other relevant component dates can be seen.
1st October
To accompany the previous entry, the Jennings advert, placed in "Melody Maker" magazine, 1st May, 1954, for the BIF Fair of that year, held at Olympia in London. The ad has been said to contain the earliest mention of a "VOX" amplifier. Note the output - 15 to 25 watts. This was certainly not Derek Underdown's G1/10 - possibly a version of his "30 Watt Amplifier"?.
If "Accordion Times", April 1954, turns out to have an ad along the lines of the one published in April 1955, it will be posted here.
"Melody Maker" magazine, 1st May, 1954. Note also the "Rotary Foot Swell Ccontrol" (first advertised by Jennings some months earlier). Rotary foot pedals were further developed by Tom Jennings's post-JMI company - "Jennings Electronic Industries" (late 1968 to 1975). But in the 1950s Jennings as ever, was not without competition - Selmer had its own rotary foot pedal. Selmer and Jennings played leap-frog with other things too.