Vox AC30 website updates
2021
1st November
Some pages coming soon on the Brimar valves used in AC30s. Below, an advert from 1962 promoting among other things, Brimar-made ECC82s and ECC83s.
Electrical trade journal, February 1962.
30th October (2)
Just to note in relation to the entry below that Selmer also produced perspex amplifiers for Trade Fairs - the first in 1965, probably copying JMI.
But JMI, for its part, had probably borrowed the idea too, taking its cue from the perspex radios and television sets shown at the National Radio Show at Earl's Court in the early sixties and perhaps late fifties.
Music trade journal, November 1966. A perspex Selmer Zodiac (not Thunderbird as originally stated), displayed at the 2nd Dutch Musical Instrument Fair, Hilversum, October 1966.
30th October
A short report in the music trade press following the Russell Hotel Fair of August 1963 - JMI's (first) perspex AC30. The page on these amps - here - has been corrected and updated.
29th October
An AC30 (1963) signed by Dick Denney in 2001 is pictured on John Beer's Amp-Fix site.
26th October
The Amperex sheets for the EL84 have been added to the valve data section of the website. These are dated November 1956, with revisions, August 1957.
24th October
A new "Links" page has been started, accessible on the banner at the head of this page and via the sitemap. There are also new pages for the GZ34 and ECC83 data sheets embodied in the Amperex manual pictured below - they can be found here. It seemed useful to give the Amperex data alongside the Mullard (posted a little while ago), as the former's is more extensive.
23rd October (2)
The third volume of a three volume valve (tube) and semi-conductor manual issued by Amperex in 1965. Among the valves encompassed are the GZ34, EL34, EL84, ECC82 and ECC83. Some of the data-sheets came from Philips, others from Mullard.
Certainly where AC50s and AC100s are concerned, replacement valves provided in America generally seem to have been branded "GE" = General Electric, or "RCA" (Radio Corporation of America) - presumably because Thomas Organ Service Centers had accounts with these companies. But Amperex will doubtless have been used from time to time too.
The valves used in guitar amps normally come under the heading of "Special Purpose Tubes" in manuals published in the USA in the 1960s.
On an only slightly related note, there is the question of whether JMI set the voltage selectors of amps ordered by Thomas Organ to 115v before packing them up for dispatch. Possibly not. It may be that this was left to local shops or dealers.
23rd October
Thanks to Geoff and Lewis, further pictures (details) of AC30 serial number 18128, first half of 1965. Woden mains transformer and choke - date codes "HV" and "JV" = August and September 1964. The output transformer is a Parmeko, marked with the JMI part no. 66314.
In the preamp: the main filter capacitor has "VG" = August '64; mullard capacitors with "B4N" and "C/64" = second and third quarters of '64; and blue Hunts 25uf cathode bypass caps with "IIT" = 33rd week of '64. One of the original yellow-print Mullard ECC83s has the paint code "LI" = September '64.
In the power section, the TCC cathode bypass cap for the EL84s has "VJ" = September '64.
One of the date codes on the silver Celestion T1088s is just readable - either "02HJ" (2nd Aug. 1964) or more likely "02MJ" = 2nd December '64.
22nd October (3)
From mid 1963 to mid 1964, the Thomas Organ Company shipped its organs to Dartford Road already assembled for distribution in the United Kingdom by JMI. See the picture lower down this page, entry for 12th September.
In late 1964, things changed however. Jennings created a "Thomas Organ Division", placing adverts for a head of section in the music trade press and local Dartford newspapers. It may be that Geoff Harris, an existing JMI employee (a production engineer), was appointed. He certainly headed the division in 1967.
At any rate, in late 1964 Thomas began sending its organs in component form - i.e. to be assembled and checked in England. Whether these continued to go to Dartford Road rather than the newly opened Vox Works at Erith is not known definitively at present. The former though seems most likely. More on the relationship between Thomas and JMI to come.
November 1965.
22nd October (2)
Some new pictures of AC30 Twin serial number 18128 coming shortly, thanks to Geoff and Lewis.
22nd October
Thanks to Jet, pictures of Super Reverb Twin serial number 4313B, complete with its Burndept inspection tag. Further pictures can be found here.
20th October
Thanks to Martin, pictures of AC30 Super Reverb Twin serial number 10322N, probably early 1964, originally sold by Servaas in The Hague. Further pictures can be found here.
18th October
Copied over from the Vox AC100 website updates page, a shot of the JMI stand at the Russell Hotel Trade Fair, August 1965 - an AC30 in view along with the new LS60 column speakers and a pre-production, perhaps even prototype (though that's a much mis-used term) two-manual Continental. By the time production came, the design of the Continental was changed, and it changed again shortly after that. See the pictures in the "Dual Continentals" section on the Combo Organ Heaven website.
August 1965.
12th October
December 1951 - a detail from a Jennings advert illustrating and describing the "Univox" amplifier, the earliest dated instance of the amp that has emerged to date. An overview of early Jennings Organ Company and Jennings Musical Industries amplifiers can be seen on this page.
December 1951.
10th October
A page has now been started on Jennings organs in 1953 - the J51 and probably a first version single manual J50.
9th October
A copy of the original studio shot of the Vox Continental from late 1962, printed in a music trade journal in 1963, hand-written legend at foot. JMI often supplied journals with original photos. The image was used in adverts through to 1964 in a variety of forms - masked; as a "cut-out" on a plain white background (with and without text overlay); on coloured backgrounds (catalogues and brochures); and as the basis for new graphical (ie. hand-drawn) art work.
Music trade journal, August 1963.
Detail from the Continental brochure of mid 1964. New art work based on the original studio shot.
8th October
The choke of AC30 serial number 22789, date code "KY" = October 1967, ie. produced by Woden, which was based in Bilston near Wolverhampton (West Midlands), two months before the amp had its final inspection. See the entry for 30th September lower down this page.
Below, a shot of the Woden factory from the Wolverhampton Express and Star Archive.
Woden factory, c. 1976.
7th October
In May 1954, Jennings attended the "British Industries Fair" in London, Olympia, displaying among other things its J50, J51 and J52 console organs. Reviews were favourable, and the music trade press provided some account of the design process - see this page - which seemed to suggest that the organs were new that year.
As it turns out, the J51 was certainly not new, having been displayed and demonstrated at the "British Industries Fair" in 1953. The demonstrator was Robin Richmond, who worked for JMI through to early 1954.
Whether the J50 and J52 were shown in 1953 is unknown at present - probably not. JMI certainly placed no adverts for the organs in the music journals of 1953.
Music trade journal, May 1953. Surrounding the organ are adverts for the Univox, and an example with a "gigster" stand.
3rd October
Three paragraphs from an interview with Tom following JMI's "Queen's Award for Industry" in Spring 1967 - a long piece published in the local Dartford newspaper. His recollection of the first "V.O.X." amplifier seems on the face of things slightly off - the first amp to bear the name "Vox" appeared in 1954 rather than 1956 (see the advert below). However, it is possible that Tom had the G1/10 in mind - designed by Derek Underdown, shown in preliminary form at the "British Industries Fair" of April 1955, and probably not in production proper until 1956.
An overview of the various types of amplifier sold and made by Jennings through to 1957 can be found on this page.
Local Dartford newspaper, April 1967.
"Melody Maker" magazine, 1st May, 1954 - advert for the "British Industries Fair".
2nd October
A snippet from a piece on Tom Jennings published in an electronics trade magazine, December 1964. Apologies for the bendiness. Interesting to see the statement that JMI amplifiers were "creating sound". Perhaps Selmer said such things about the "Selectortone" circuit of its Twin Thirty.
As for patented vibrato and reverb circuits.... - a good line to cool the heels of the competition, but at present without firm evidence. Note that the circuits are envisaged also as add-ons units to PA amplifiers / systems. This was certainly the thinking behind the "All-in-One" PA amp shown at the Russell Hotel Trade Fair in August '64. But it never found its way into production.
At least one Vox Continental organ has a "patent applied for" plaque (in respect of the keyboard contact assembly) fixed inside its cabinet, but the staff of the British Library Intellectual Properties department have so far failed to find any sign of the application in the Patents Office records. The claim in adverts that "world patents" were held for the organ relate solely to the drawbar circuits, designed by Derek Underdown in the late 1950s for console organs. Tom was a clever old thing.
Thanks to Martin for the reference to the article from which the excerpt below comes.
Updates for October and November 2020.