webpage

Vox AC30 website updates

September 2025

30th September (2)

Posted on the updates page of the Vox AC100 website recently: - local press, late January 1967, a double spread on the West Street Works at Erith, the famous picture of the final assembly / dispatch hall (top left) printed in full, ie. uncropped.

Larger images of the three shots taken in the Organ Department (on the top floor), can be seen here.

"Twang Goes a Million" - the West Street Works.

30th September

Dallas-made AC30s, 1974 to 1977: two rows of metal vents (painted black) of three types: (1) plain, six open "compartments" of equal size; (2) a central panel with a VOX logo in cursive; (3) a central panel but no logo. (1) and (2) may be old "Vox Sound Limited" stock.

The Dallas amps for the most part either have (1) and (2), or (1) and (3). A few have all (1) or all (2).

A detail from a Dallas-made AC30, late 1975 / early 1976, types (1) and (3).

As a sort of aside, below, a recovered AC30 of unknown type (either Italian-made or perhaps one produced by Dallas) with vents screwed into the top of the cabinet - an interesting workaround for broken locating pins:

29th September (2)

Spring 1964, a couple of nicely melted vents. The third is fine. Plastic was not a particularly good choice of material, especially following the reduction in value of the bias resistor (from 80 to 50 ohms in later 1963) - the result being appreciably hotter EL84s.

Further notes (at intervals) to come this week on vents, to be collected together eventually on a page of their own.

Vents directly above the EL84s.

29th September

Two chassis signed off at Westrex in early 1963 by Thelsa, one used for AC30 Super Twin serial number 6855, the other for a Twin serial number unknown.

AC30 Super Twin serial number 6855.

AC30 Twin, number unknown.

A colleague signed chassis off with the initials "DP", first occurence currently known in the chassis used for serial number 6000, later instances through to later 1964 (Super Twin serial number 3349).

AC30 serial number 6000.

28th September (2)

The note mentioned below has been expanded to take account of Reg Clark's recollection (reported by Jim Elyea) that the first batches of black vents, introduced across various models, were made of plastic. Whether they actually made their way onto AC30s requires further investigation though.

Number 6898 has plastic - but are they originals or repros? The latter is certainly possible as someone added repro two-pin corner protectors to the cabinet. Conversely, one has to question the originality of the metal vents on the cabinet of serial number 6664, re-covered at least once over the years.

Serial number 6885 also with metal vents has been recovered. Serial number 7005 looks to be OK.

The task is therefore to identify as definitively as possible early black plastic vents still in situ on their original cabinet.

28th September

A note has been added towards the end of the page on AC30s with serial numbers in the 6000s to mark the first appearance of black metal cabinet vents.

Some care is needed these days though as black plastic repros have been around for some time, not to mention the modern production (ever-so-slightly-too-thin) brass ones.

26th September

Just to note that a first set of updates has now been made to the page on Wodens. To come, a section on 1967 (known date codes, etc.), and the addition of short digests of notes kindly supplied by Philippe on the three main types of Woden output transformer construction:

I: autumn 1962 to early 1964: green enamelled cover; doubled wires for the taps to the terminal block; doubled red wires for the HT; windings wrapped in adhesive paper or paper/cloth tape, wax potted.

January 1963.

II: late 1964: single wires to the terminal block taps; a single red wire for the HT; windings wrapped in plain paper/cardboard (a single width); construction generally as the output transformers produced by Parmeko and Albion for JMI.

October 1964.

III: Spring 1965 to 1968: as above, but a return to adhesive paper tape, varnished outer wrap and underside (first lamination).

November 1966.

25th September

The page on Woden transformers is in the process of being updated with notes on the use by JMI of units with 1964 and 1965 date codes.

Thanks to information supplied by Philippe, the main overview page on transformers will be updated shortly.

23rd September

A number of entries on the page for the Vox Domino Bass have now been updated with pictures. More to follow on the Domino range shortly.

22nd September

A note on the new-style VOX logo: - used by Jennings from late 1966 for its solid state range (amplifiers, speaker cabinets, and certain organs); and from late 1967 on AC30 Twins and Super Twin speaker cabinets, the earliest Twin currently known being number 22789, final inspection December 1967, the earliest Super Twin set being number 5600 (the logo on the cabinet since changed).

AC30 Twin serial number 22847.

That no Super Twin amplifier section has come to light so far with this type of logo tends to add to the feeling that in later 1967 JMI had good numbers of units that had been made ready for sale (final assembly, checking, etc.) some months earlier.

Where AC50s are concerned, the new logo first appears in the low 7400s, becoming increasingly common thereafter - see this page on the Vox AC50 website. No instance of such a logo fitted at factory has surfaced yet on an AC100.

In late '67, final assembly / cabinet finishing took place at the Vox Works in Erith. Below, a shot of the benches in Dartford Road days, AC10s, AC30s, and AC50 speaker cabs being made ready. Serial number plates were added - and numbers assigned - by Jack Jennings and his team once final testing (and inspection) had taken place.

115 Dartford Road, late July 1964, cabinets in the process of being fitted out with chassis, speakers, logos, handles, etc. In the background just off centre and without a white coat is Doug, one of the testers. Along the left-hand wall, the testing booths. Thanks to Bob for the picture.

20th September

Thanks to Jos, pictures of AC30 Super Twin serial number 5610, later 1967, close to the end of JMI's run. The amp was purchased in May 1968. An entry to follow on the later Super Twins page.

Just to add (as a general point of reference) that an AC30 Super Twin speaker cabinet that turned up in the UK last year also with an original long new-style logo had speakers dated 4th August 1967, indicating that it may have been ready for sale as early as September, although it has to be said that AC30s did not move at all quickly in later 1967.

AC30 Super Twin serial number 5610.

19th September

The last of the ads for "Musicland" placed by Tom and Reg Clark in "Exchange and Mart" magazine, September to December 1965 - very much of their time and just a little bit naff (as many of the illustrated ads in Ex. and M. were).

18th September

Thanks to Joris and Jeffrey, pictures of single-speaker AC10 serial number 4571, still in superb condition, have been added here.

AC10 serial number 4571.

17th September

A detail from the instruction sheet supplied by JMI with its Line Source 40 column speakers showing the requisite connections at the speaker terminal blocks of Vox amplifiers.

AC30s are generally fairly consistent in the arrangement of their 8ohm and 16ohm taps, conforming in the main to the order given in the schemas, the only inconsistency being the colours of the leads issuing from the transformers - brown (8 ohms), black (comm), green (16 ohms) for some earlier Wodens; green (8 ohms), black (comm), blue (16 ohms) for Albions and other Wodens.

AC30 Super Twin amplifier sections twinned with Line Source columns - for Public Address purposes - were surprisingly popular in the 1960s.

Early AC80/100s and AC50s are a case apart. The common in the former was generally the lowest terminal of the three. AC50s often had common at top. But as XLR speaker sockets were generally standard on the back panels of these amps, the relative order of connections did not matter just so long as they were correct in relation to those on the socket.

AC30 Super Twin IIs and Super Reverb Twin IIs normally also had XLR sockets on their back panels.

Detail of an AC30 Public Address set from late 1963 / early 1964 - Super Twin amplifier section, two LS40 speaker cabinets - still with its original cables. Two ends have XLR sockets to plug into the speakers, the other two have bare wires screwed into the 8 ohm tap of the amplifier's terminal block, as illustrated in the guide above: "Two in parallel at 15 ohms each".

16th September

Six new entries have been added to the page on AC30s with serial numbers in the 11000s: 11078N, 11640B, 11746B, 11768T, 11820T, and 11862B.

15th September

Thanks to Martin, a couple of shots of the two versions of JMI's "Vox Amplification Precision in Sound" brochure, mid and later 1963, bridging the transition from fawn to black vinyl. The later version of the brochure is much more common. Copies, poorly photocopied in colour, were widely circulated in the early 2000s.

1963.

14th September

October 1968, "Exchange and Mart" magazine, empty single-speaker Vox AC15 cabinets (and 2x15"s) doubtless acquired by the seller at one of the JMI liquidation sales. The "790" in the telephone number indicates Stepney Green.

Another seller - in Ilford - also offered empty (unused) AC15 and AC50 cabs for sale in October '68. Stepney and Ilford are a short distance from Hainault, where Gla-Rev, one of JMI's principal cabinet makers, was based - perhaps only coincidence though.

Given that the single-speaker AC15 was discontinued in 1965, the cabinets in view are likely to have been in storage for at least a couple of years by the time they came up for sale.

October 1968.

13th September

Some new / updated entries for the page on AC30 Twins with serial numbers in the 10000s: 10227B; 10405N (but actually / currently a TB); 10408N (also actually / currently TB); and 10472N (plate no longer on the original amp).

12th September

One of the latest Univox J6s currently known, late 1964 / 1965 - serial number 3617, split front, black grille cloth, black basketweave vinyl.

The interior of the cabinet to show the unfaded black cloth.

11th September

A Vox Conversion Unit belonging to a Univox J6 from the later 1950s. It measures around 7" wide, 2 1/2" tall; and 6" deep. Jennings literature notes its weight as being 16 ounces.

The inputs are captioned (top to bottom): "Moving Coil or Ribbon Mic"; "Crystal Mic"; "Gram[ophone]".

10th September

Univox J6 serial number 3591, split front, one of the last to have been produced in faux croc skin vinyl, probably 1963.

Documentation, case keys, volume bar, and plate to mount the keyboard beneath the keyboard of a piano.

8th September

A new page has been started on the Vox Conversion Unit, 1955 - c. 1960 - click on the picture link below.

7th September

The "Nite Riders" with two beige AC30 Super Twins with early tray stands. Further early stands can be seen on this page. The "VOX" logo of the one on the right can just be made out in the detail below.

"VOX" logo just visible on the front of the stand.

6th September

A further AC30 Super Twin with its BASS flag up by the VOX logo - supplied to "The Eagles" by JMI following the theft of their equipment in October 1962. The pics have now been added to the page on these BASS flags.

October 1962.

Detail from the cover of the band's EP on the Vogue label in France, 1962.

Cardiff, May 1963, backing Del Shannon.

5th September

Added to the page on AC30 Twins with serial numbers in the 17000s, text entries for numbers 17118T, 17157TB, 17201T, 17232TB, 17478T, 17642B, and 17983TB. Select pictures to follow.

4th September

Two panels with later holes, purpose unknown, in almost exactly the same place: the upper picture is of a panel for sale in Europe, the lower of AC30 Super Twin serial number 2503, recently sold in the UK, the holes in the panel apparently leading nowhere, the right-hand one slightly closer to the JMI logo than the corresponding hole in the panel pictured above it.

What were these holes for, and why in these two panels?

3rd September

A (genuine) AC30 in red vinyl for sale in South London, late 1964. The "gold" is probably a reference to the fine gold thread woven into certain batches of brown grille cloth commissioned (and used from time to time) by JMI in 1963 and 1964.

Be doubly - triply - careful these days if you encounter a red AC30 Twin presented by the seller as somehow being "original" - either in "his opinion" or that of some unnamed "former JMI man". A number of AC30 Twins with copper control panels were recovered in red a few years ago. At least four of these spanky-looking non-original red amps are known.

September 1964.

December 1964.

The page on AC30s finished in coloured vinyl by / for JMI can be found here - further material to be added shortly.

2nd September (2)

Also to note in relation to the entry below that certain Westrex-made AC30 and AC80/100 chassis have hand-written numbers, all apparently written by the same person: 119, 130, and 165. The significance of 130 and 165 is not clear at present.

2nd September

Two AC30 Treble chassis assembled for JMI by Westrex, both stamped in purple with "Westrex Treble" and "119" (119 Dartford Road). Most Treble chassis assembled by Westrex apparently only have the former. Whether "119" was simply omitted in the majority of cases or rubbed away later is not known for certain - on balance, the latter seems more likely. Why stamp only certain chassis in this way?