Vox AC30 timeline
1957 - autumn 1961
2nd August 1951: Tom applies for a trademark for the name "VOX", granted on the 8th October 1952.
2nd August 1951: Tom applies for a trademark for the name "Vibravox", granted on the 6th January 1954.
Autumn 1957 - April 1958: The AC2/30 is reviewed in September 1957 and from November advertised in "Melody Maker" and "Accordion Times". At least four different AC2/30s are illustrated in Jennings promotional material. See this page.
December 1957: The new AC1/15 is first advertised (in "Accordion Times") - also on the page linked above.
June 1959 - May 1960 (possibly beyond): The AC/30 is advertised. See the second half of this page.
Early 1960: JMI becomes agent for Fender amplifiers, guitars, and accessories in the UK. A coloured brochure is produced in autumn 1960. An extensive JMI pricelist from late 1961 survives.
April 1960 : The Music Trade press reports a new range of Vox amps, including the AC30 Twin (TV Front) and the AC30 Bass - "One model has a bass frequency amplifier and a twin speaker amplifier.
29th April 1960: The circuits for the AC30/4 and AC30/6 are drawn up. The circuit diagrams (schematics) are dated 29th April 1960. Modifications for the AC30/4 "Bass" model are indicated on OA32. OA31, the circuit diagram for the AC15, also bears the date 29th April 1960. "Normal" and "Bass" models are likewise noted.
30th April 1960: "Melody Maker" magazine indicates that "Normal" and "Bass" AC15s were available - the day after the circuit diagram had been drawn. "Normal" and "Bass" versions of the single speaker TV Front AC/30 are also advertised.
May 1960: The AC30 TWIN is referenced in the pricelist of Spring 1960 and "Accordion Times", May 1960. This is the TV Front AC30/4 twin, price 100 guineas.
May 1960: It is expressly stated - "Accordion Times", May 1960 - that "Bass" amplifier models are for accordion.
Spring to late Summer 1960: The TV Front twins - AC2/30 and AC30/4 circuits. The page on these amps has been readjusted. Pictures showing Billy Fury on stage in front of two TV front AC30s are sometimes said to have been taken at the NME Pollwinners Concert, February 1960. They are actually from the NME Concert of 1961.
July 1960 - : "New Vox Amplifiers" are advertised; and simultaneously the AC30/6 makes its first advertised appearance - two ads in "Melody Maker", 30th July, 1960, price 89 guineas. Probably at this point, the new split front box for the AC30/6 was introduced - see this page for the black panel AC30/6. No TV Front AC30/6s are known.
Late autumn 1960: The first split-front AC15 appears. The lowest serial number known at present is 4208. The highest number for a TV Front AC15 is 4184.
19th November 1960: The "VOX 30 Watt, 6 input, TWIN vibrato" is 89 guineas, the price given in July 1960. "Normal" and "Bass" versions of the AC30/4 are available.
December 1960: The Shadows receive three new TV Front AC30s along with two tall stands for Bruce and Hank's amps, and one shorter one for Jet Harris's.
Between December 1960 and January 1961: The Celestion T530 blue is introduced. Prior to that the T530 had a hammertone/oyster finish, as the CT3757.
January 1961: JMI becomes agent / distributor of Wurlitzer entertainment organs in southern England. The arrangement lasts around a year.
February 1961: the AC30/4 and AC30/6 circuits are modified slightly (one change).
March 1961 - : The Shadows are first seen with new split front AC30/6s in black.
May 1961: A new circuit is introduced. Changes are noted on the circuit diagram - the "List of Changes" (LOC). The new AC30/6 is advertised in "Melody Maker" - on this page.
May/June 1961: Westrex is contracted by JMI to produce the "new circuit" AC30/6. Production of the AC30/4 remains at 115 Dartford Road.
July 1961: JMI announces the new "Stereophonic Series" of amplifiers, in actual fact the Super Twin - separate amplifier and speaker cabinet with closed back. "Stereophonic" was JMI's initial term for the Top Boost circuit.
Mid 1961: AC30/4s are designated "AC30 4W" on their serial number plates, AC30/6s are "AC30 6W". In the first half of 1961 the two versions are simply "AC30 W".
Mid 1961: Bass versions of the AC30/6 are for the first time designated with a "B" on their serial number plates.
25th September 1961: Tom applies to trademark the name "Vox Supertwin".
23rd September 1961: The final appearance of the AC30/4 in ads placed by JMI in "Melody Maker" magazine.
A collection of documents relating to 1960 and 1961 is available here.
Copper panels and beige cabinets (mostly)
Last quarter of 1961: The new copper panels make their first appearance on amps with serial numbers in in the high 4000s - see this page.
28th September 1961: The first advert placed by JMI in "Melody Maker" magazine for the new AC30 Super Twin - the "Super Twin de Luxe".
October 1961: the AC30/4 is officially phased out. The Super Twin (separate amplifier and speaker cabinet or cabinets) is promoted, described as having "a special tone unit with extra controls at rear" = Top Boost. The pricelist of October '61 gives prices for two versions of the Super Twin - the "Super Twin/1" with one speaker cabinet, and the "Super Twin/2" with two.
11th December 1961: the circuit diagram for the Top Boost circuit drawn out.
Copper panels; beige and black cabinets
Early 1962: JMI contracts Triumph Electronics in Purley to produced AC2 / AC4 chassis.
Autumn 1962: Burndept Electronics (Erith) is contracted to make AC30 chassis. Westrex continues to make chassis too. Burndept uses transformers (with green shrouds) made by Woden. The earliest batches have date codes "HT" = August 1962.
August 1962: George Harrison has a beige AC30 Twin with top boost controls on the back panel.
Late August 1962: JMI unveils the T60 Bass and AC30 Super Transonic amplifiers, along with the new Vox Continental organ, at the Russell Hotel Trade Fair in London.
12th December 1962: JMI advert in "Melody Maker" magazine for the Super Reverb/Twin/I and the Super Reverb/Twin/II - reverb being new.
From late 1962: Black vinyl covering - "dimpled" or "pebble" - begins to predominate, serial numbers in the high 6000s.
Copper panels; black cabinets (mostly)
Late December 1962 / early January 1963 : John Lennon and George Harrison are issued with new AC30s in black covering.
29th January 1963: Tom Jennings sells JMI's shares to Royston Industries, joining Burndept as a member of the Royston Group of Companies.
Early 1963: new plastic injection-moulded handles come in.
1963 : Batches of Woden transformers arrive with date codes "AU" = January 1963; and "HU", "JU" and "KU" = August, September, and October 1963. October '63 Wodens are found in amps with serial numbers in the high 9000s.
22nd February 1963: Tom begins the process of trademarking Vox grille cloth.
28th March 1963 : JMI applied for the trade mark "Twin 30". This was granted in September, the success of the application published in the music trade press.
Last quarter of 1963: Basket-weave vinyl is introduced, though some cabinets are still finished in "pebble".
End of 1963: one begins to see new black vents on top of Twin cabinets instead of brass.
Late December '63: the last time The Beatles use AC30s on stage as their main amps. Paul is issued with a new AC80/100 and John and George receive AC50s. The band does however use a new AC30 live in 1965 for the Vox Continental organ.
A collection of documents relating to 1963 is available here.
Copper panels; black cabinets
1964 : A new batch of Woden transformers comes in with date code "MU" = December 1963, and "AV" = January 1964.
Late January: An advert for the AC30 Extended Frequency (15" speakers) in "Melody Maker" magazine.
Early Spring '64: the first grey panels make their appearance.
Early Spring '64: the Treble model is introduced, chassis produced mainly by Burndept.
Summer '64: the first silver Celestion alnicos (T1088) appear. Vox commissions a new style of transformer from Woden - plain metal shrouds and for the output transformer, a less complex internal structure.
August '64: at the Russell Hotel Trade Fair, a new look for Vox amplifiers is announced. This was black grille cloth. Grey panels had already made their appearance in the Spring.
A collection of documents relating to 1964 is available here.
To be continued...