31st August

For the time being, the last of the details of the Lightweight cabinet - the upper back board. Further aspects will be illustrated in course. These cabinets were certainly the most complex - and perhaps approaching the most expensive - commissioned by JMI in the 1960s.

Upper board of serial number 15205L. Vinyl was removed to cover the cutout for the tremolo module, the backing plate of the module (with its cutouts for inputs and controls) used as reinforcement. The runner along the upper edge supports the underside of the slider board.

30th August

The inner face of the AC30 Lightweight baffle. Around the edge a sort of lower "border", 3/4" wide, 3/16" deep, to help the baffle sit tight up against the inner runners of the cabinet - a further cost in what will already have been an expensive item.

29th August

General dimensions of the Lightweight's baffle have been added below. Also to note that the tremolo module of serial number 15205L was removed at some point and the cutout for it in the upper back panel blanked off. Probably at that time too the amp was fitted with standard AC30 swivel side stands. Pictures to come.

28th August (2)

It may be useful to give some dimensions of the standard AC30 Lightweight as (i) JMI only noted the size of the later short-lived version with front-facing controls; and (ii) Jim Elyea, page 424, gives dimensions for something other than the standard amp.

Overall size: 24" wide x 21 1/2" tall x 11" deep. The top, bottom, and sides are 3/8" birch ply. Internal runners/braces are 3/4" square.

Slider board: 23 3/16" long x 9 5/8" wide x 3/8" thick. The cut-out is 13 7/16" long x 5 1/2" wide. The cutaway, to avoid the speaker, is 9 3/4" wide along the outer edge of the board, tapering to 5 3/4". It is 1 7/8" deep.

Baffle: 23" wide x 19 1/8" tall x 3/8" thick. The cutouts for the speakers are 8 1/2 in diameter, the centre bar in each 3/4" wide.

Fixing screws for the back boards are 2BA. All other screws - set screws on the baffle, internal fixings - are 4BA.

28th August

The slider board and T60 chassis of AC30 Lightweight serial number 15205L (plate pictured below, 26th August). The cutaway was required to keep the board clear of the topmost speaker.

The views are of the underside of the board, when mounted in the cabinet the transformer hanging down into the speaker compartment.

27th August

Late 1964, just passing by, a two-input AC10, either a really early one, or an early second-circuit amp; and an early AC30, probably a TV Front Twin given the price.

October 1964.

December 1964.

26th August

Recently come to light, AC30 Transistor Lightweight serial number 15205L, not quite the latest currently known (which is 15247L), but close nonetheless to the end of the model's run - at least as JMI formulated it. More to come on the amp in due course.

AC30 serial number 15205 L.

24th August

A (genuine) puzzle plate, stamped "4056 N". This appears on the amplifier section of a Super Twin set, originally a Super Twin 2.

"4056" is wrong for a Twin of any sort. Nor did the plate belong originally to a single speaker AC30. The designation "N" ("Normal" voicing) in any case only came in later.

The original thought - that "4056" was a mistake for "5056" - now turns out to be incorrect. The chassis was produced by Burndept and has Woden transformers with enamel green shrouds. Thanks to Brent for pictures. Burndept first began assembling chassis for AC30 Twins in later 1962 - starting at around serial number 5600 - the earliest Wodens dated August '62.

Was the number supposed to be 5640 or something along those lines? Hard to say. At any rate, the amp is a great example of a scarce model.

Rear of the amp.

"4056 N", original fixing screws.

22nd August

March 1966, an AC30 Transistor Lightweight. In late 1964 list price was £94 10s. The model was not by any measure one of JMI's best sellers.

March 1966.

21st August

The "extra amplifier" mentioned in the small ad from December 1963 in yesterday's entry is what JMI called a "Conversion Unit", developed in late 1955 and advertised through to the later 1950s. Thanks to Glen Lambert for making the connection.

Also to note that around 18 months earlier in "Exchange and Mart" (in May 1962) another appears to be referenced - termed a "mixer unit" - in conjunction with a "Univox J2" (most likely a J7).

Detail from the JMI catalogue of Spring 1958.

20th August

December 1963, mention of an "extra amplifier" - presumably a sort of preamp - provided by JMI for the Univox J10 enabling other devices to be plugged in and amplified alongside the keyboard.

December 1963.

19th August

December 1967, an AC30 Super Reverb Twin II "out in the wild". It is unlikely that JMI sold many of these sets. Only one other has come to light so far in magazine small ads.

December 1967.

18th August

Thanks to Jez, some details of AC30/6 serial number 4706B - probably ready for sale in September/October 1961. Some work in the preamp (and on the cabinet) in the 1970s, but still going strong.

An overview of AC30/6 twins with black control panels can be found on this page.

17th August

For most of 1967, "Exchange and Mart" magazine presents a fairly unremarkable turnover of Vox amps - mostly AC30s, other models here and there. The one major exception - forty discontinued AC10s on offer in an antiques shop in Erith in February 1967 - is outlined in yesterday's entry.

In late 1967 / early 1968 things change - a huge tide of Vox equipment sweeps in, most of it described as being "as new" or between one and three months old, the items in view doubtless having been picked up at the various surplus/liquidation sales at Dartford Road and the Vox Works in Erith. Three sellers appear to have bought a van load (amps, empty speaker cabs, etc.) each.

Bound "Exchange and Mart" (weekly) magazines, 1967 and 1968.

Notable in the listings are numbers of "AC30 Lightweights". These in fact were "partsters" - "lash-ups" if you like - either cobbled together for sale by someone at JMI in late 1967, or by a buyer who bought the chassis, cabs, and so on, separately.

No two amps are the same. They are not mentioned in any JMI pricelist, catalogue, or brochure. None has a serial number plate. Chassis are surplus AC10 or Domino Super Reverb Twin chassis.

The AC30 Lightweight proper - i.e. as produced by JMI in 1964 - was fully transistorised and had no reverb. An overview of the partster amps of 1967 / 1968 can be found on this page. Below, some of the listings. No listings for Lightweights of any sort were placed in 1967.

March 1968, the first "Lightweight" listed in "Exchange and Mart" for at least 15 months.

April 1968, word spreads. Farningham is in Kent.

August 1968. At least two different types of Goodmans are known in these amps. The seller was in Hainault, East London.

August 1968, a seller in Leytonstone, East London. Beneath his listing, a listing for a Guitar Organ by the seller in Hainault.

December 1968. A seller in Grays, Essex, with loose Domino Super Reverb Twin chassis, no speakers, no cabinets.

In 1969, listings of Vox equipment return pretty much to normal, i.e. much as they were in 1967, primarily AC30s, other models / types here and there.

16th August

Just to signal that a number of entries for single-speaker AC10s have recently been updated. Others to be tackled shortly. The Twins registered on that page will remain in place for the time being as they provide useful stepping stones. The two models shared a single serial number sequence into 1964. Twins were considerably more popular than the single-speaker amps.

Below, some (unusual) listings for AC10s from the later 1960s. First, forty Super Twins, presumably cleared out from the Vox Works in Erith in late 1966 / early 1967, acquired by the "Antique Shop" a few doors down on West Street. The second ad notes that the amps, termed Twins rather than Super Twins, had T/B = "Top Boost" - strange for an AC10. It may be that they were in fact old-style AC10 Super Reverb Twins, the seller simply mistaking the controls on the back panel for those of a Top Boost module.

2nd February 1967.

February 1967. Same telephone number as above. In late 1966 the seller had undisclosed models and numbers of Vox guitars and amps for sale. A pretty peculiar Antique Shop.

Second, another seller a month or so later claimed to have an AC10 Twin with a chrome swivel stand. Did he mean swivel side legs?

April 1967.

Below, a late-production AC10 Super Reverb Twin with a full-frame trolley - in all likelihood a JMI original. Details show that the handwheels with distinctive incised VOX logos are identical to the ones used on early AC100 Super de Luxe trolleys. Further notes on this amp and the late-form model in general to come.

15th August

May 1962, a puzzling listing: an AC30 with an "echo chamber" of some sort fully incorporated, along with a volume pedal and microphone. If the "18 months old" refers to everything in view, as it seems to, then the AC30 is likely to have been a TV Front twin. Quite how the echo unit - Vox (Meazzi) or not - might have been "incorporated" in the amplifier is impossible to tell.

It feels as though the equipment belonged to a solo performer (a singer-guitarist).

May 1962.

14th August (2)

Exchange and Mart, 1962, the five main varieties of advert for Musicland placed by JMI in the magazine. On 26th July, the price of the AC4 evidently went up from 19 to 22 guineas, an increase not reflected however in the pricelists issued by the Jennings shop on Charing Cross Road.

From May to mid July amplifiers at 19 AND 35 guineas are quoted - i.e. the AC4 and the two-input AC10 with vibrato (tremolo) rather than vibravox.

1962.

14th August

Exchange and Mart magazine, March 1967, mention of a Vox Continental dual manual having been purchased in April 1966 - i.e. early on (in terms of production proper).

A page on the earliest (in some cases pre-production) Continental dual manuals can be found here.

March 1967.

13th August

Below, what must be one of the very latest Celestion T1088s to have been made ready for use in a speaker compartment or cabinet by JMI - dated "7CA" = 7th March 1968 for its manufacture in Celestion's factory in Thames Ditton.

12th August (2)

Picking up from the entry below, three repro plates, suitably "aged", with spikey modern stamped numbers, offered for sale in 2020 - 5802, 6344(?), and 6603. Someone clearly has a penchant for faking up plates with numbers in the 5000s and 6000s. Beware!

12th August

It was stated on this page that the person who stamped a series of reproduction plates with distinctively spikey non-original (modern) numbers was Eric Snowball, a former JMI employee who set up in business for himself in late 1968 (following JMI's collapse earlier in the year). ESE Music in Maidstone was his shop (through to 2014).

Repro plates - often quite dismal and shoddily made, as below - were normally sold by their maker/manufacturer(s) with blank panels. Which is not to complain. The errors and inaccuracies of typography enable these plates to be spotted a mile off.

A question mark must now be placed over Snowball's part. Below, the plate of a highly suspect Vox UL430 that passed through the hands of two well known businesses six or so years ago. Repro plate, the same set of stamps as above. The story surrounding the "appearance" of this 430 was utter hogwash.

Fake Vox UL430 plate.

And such plates, stamped with crazy stamps, continue to surface - another four at least (three in one ebay auction) in recent years. A picture of the three will be posted soon.

Tomorrow, a genuine plate that was mis-stamped at factory by Jack Jennings or one of his team. Such errors are rare.

11th August

A couple of good details, front and back, of a control panel removed from an amp with a serial number in 5000s or 6000s - first type of AC30 copper panel.

Colour partly permeated onto the rear of the plate in the anodisation process.

10th August

Thanks to Steve, shots of the inner labelling in Univox J6 serial number 1736, keyboard assembly produced for Jennings by Herrburger Brooks in its factory in Long Eaton, Derbys. The manufacture of keyboards for Jennings console organs was contracted out (for the most part) by Tom and Derek to Kimber Allen in Swanley, Kent.

Jennings continued to use Herrburger into 1965 - for Vox Continental assemblies from late 1962. The Univox remained in the JMI catalogue through to 1967.

The page on the Continental keyboard has been updated.

Dated 1st July 1954.

9th August

A note on the liquidation/surplus sales at Dartford Road (in later 1967) and at the Vox Works in Erith (September 1968).

1967: the principal sales were prompted by the clearing out of numbers 115, 117 and 119 Dartford Road in June, and following Tom's dismissal in late September (overview of the circumstances on this page). Anthony Smith remembers being informed of the sales, which took place in number 115, the main Works space, by a Jennings employee. He picked up an AC100 chassis without a box (one of two available). The smaller sales prior to 1967 were held mainly to move particular classes of surplus stock along.

A subset of those smaller sales were the periodic sales of amplifiers that had come back from loan - sold in the main to local groups and Jennings employees at substantial discounts. The Artist's Loan Shed, managed by Alan Pyne, was behind number 119. These were fairly small beer compared to the others though.

1968: the principal sale of the contents of the Vox Works at Erith took place in September, managed by the Estate Agents John D. Wood and Chamberlain and Willows. "Vox Sound Equipment Limited" bought in a good number of amplifiers and speaker cabinets at the auction, along with furniture and ancillary fittings; items surplus to VSEL's needs (and not envisaged in its new catalogue) evidently went to individuals, dealers, and so on. To judge from the vast churn of Vox amplifiers and speaker cabinets advertised in "Exchange and Mart" in mid 1968, it looks as though some things had been already been sold at knock-down prices however - possibly in the weeks preceding and following the announcement in late April 1968 that JMI had officially ceased trading. As Rodney Angell, who worked for JMI from c. 1960, recalled, cash in late 1967 and early 1968 was king. Following the collapse (in mid December 1967) of Royston Industries, the effective owner of JMI, day to day operations, often hand to mouth, were managed by the official receiver.

Among the tide of Vox equipment listed in "Exchange and Mart", in particular T60s (probably unsold by JMI), were numbers of what sellers termed "AC30 Lightweights". More on those to come.

Below, posted on the AC100 website a couple of days ago, an advert placed in Exchange and Mart by Mr Norham in December 1968 - 14 sets of Vox Radio mics which must have come from the sale at Erith in September.

December 1968.

7th August

May 1968, the seller (in South Croydon) knows what he has. It is unusual to see this model listed in small ads or in shop ads for that matter.

May 1968

6th August

Exchange and Mart, London edition, March 1968, a single-speaker AC30 for £20. Second-hand Twins in good serviceable condition normally went for £30-£60 at this time.

March 1968

5th August

Picking up from yesterday, a further possible AC30 SRT II amplifier section, serial number in the 4800s. As in the case of known Super Twin IIs, only one speaker cabinet survives with the amp.

The arrangement is unusual in that the sockets are on the right-hand side of the back board. Speaker terminal blocks were always mounted on the other side of the chassis.

The red warning plaque is of the early type. Where AC50s and AC100s are concerned, a new version had been introduced by the time serial numbers in the 5500s (AC50s) and serial numbers in the 1200s (AC100s) became ready for sale.

4th August

A new page has now been set up for material relating to the AC30 Super Twin II, offered by JMI from late 1961 to late 1962 - a relatively short run in other words.

The general format continued, however, in the form of the AC30 Super Reverb Twin II, introduced during the course of 1962 and still on the books in 1967. Below, one of the earliest pricelists to outline the updated range.

Pricelist accompanying material supplied to Kitchen's Music Shop in Leeds in early 1963.

The only example of an AC30 SRT that has come to light so far with twin XLR sockets on its back panel is number 4691. Those, however, are later Switchcrafts.

3rd August

Thanks to Scott, a new set of pictures of AC30 Super Twin amplifier section serial number 8177N has been added here.

AC30 Super Twin serial number 8177N.

2nd August (2)

A picture page on AC30 Super Twin amplifier sections with BASS flag positioned up by the logo has now been added to the main Super Twin index.

2nd August

Thanks to Timo, pictures of AC30 Twin serial number 5801N have been added here. Entries also for serial numbers 5459N, 5687B, 5786N, and 5830B have been created / updated.

1st August

The Super Twin II: an astonishing thing the more one thinks about it, far ahead of its time. No other English manufacturer of amplifiers designed for use by guitarists and bassists produced anything remotely similar. Quite how many were made (and sold) by JMI is difficult to say. Given the price - 175 guineas in early 1962 is equivalent to around £3600 today - probably relatively few. Portability, or the difficulty thereof, will doubtless have been a factor too.

Detail from a JMI typescript pricelist, beginning of 1962.

As for other implementations of twin speaker cabinet setups by JMI (PA equipment aside), there was the T60, two 2x15" cabs recommended initially (relaxed from mid 1963); and from 1964 the twin Foundation bass cabinets of The Condors, Bill Wyman, and various others. Certain early AC50s and AC100s were fitted out with two speaker sockets for the purpose.

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