Vox AC30: copper panels
Early 1964: serial numbers in the 10000s
Serial number 10472N.
Continued from the page on AC30s with serial numbers in the 9000s. Also encompassed below, are the earliest AC30 Expanded Frequency amplifiers - AC30s with two 15" speakers in a larger cabinet, designated AC30X on their serial number plates, some chassis with top boost controls on the main panel.
One also finds at this point standard Twins and Super Twins with in-panel top boost (see serial number 10348, below).
Documents relating to the AC30 in 1964 are being assembled on this page.
Vox contracted out the assembly of AC30 chassis to two companies: Burndept Electronics in Erith, and Westrex in Dollis Hill (north London). A sure sign of production by Burndept is the presence of a stamped serial number on the aluminium upright of the preamp chassis (normally on the right hand side a little way below the voltage selector):
Detail of serial number 9916. Chassis number 02607. The sequence began at 1000, but chassis awaiting assembly were not used in any particular order.
Also indicative of production by Burndept at this stage is the presence of Woden transformers with handsome green shrouds. Serial numbers in the 10000s have date codes for late 1963 - "KU" and "MU", respectively September and December; and early 1964 - "AV" and "BV", respectively January and February:
Serial number 10317 - date codes are "KU" = October 1963, and "MU" = December 1963.
The Woden part numbers were, in order: mains transformer 72318; output transformer no. 66310; and the choke no. 66311.
A good indication that a chassis was assembled by Westrex is the presence of Albion tranformers. Dark brown 1/2 watt Dubilier resistors are found along with white Eries.
Cabinets are for the most part covered in black basketweave vinyl, though "pebble" ("dimpled") vinyl was evidently used from time to time. The pebble tended not to be so resilient, peeling off in large sections when scuffed or torn. Various examples can be seen below. Back boards as a rule now have radiused corners rather than square.
Handles during this period often have panels without "VOX logos.
Detail of serial number 10600. Serial number 10325 also has this type of handle.
Speakers in "standard" AC30s continue to be the Celestion blue (alnico magnet, Celestion part no. T530). The Expanded Frequency amplifiers initially have Celestion T900 and T1074 ceramic 15" drivers.
Serial number plates, as in previous serial number ranges, are hand stamped. Machine-stamped plates are first seen on those with numbers in the 13000s.
Just to note again, "N" indicates "Normal" voicing (schematic OA/026 and OS/065), "B" is bass voicing. No early schematic survives for the bass circuit, though in relevant respects most amps (from 1962 on) follow OS/065, drawn in September 1964. "T" denotes Treble voicing.
AC30 Twins with Treble voicing
These appear for the first time in the 10000s, the earliest currently known (Nov. 2024) being serial number 10067 - insofar as serial numbers are concerned at any rate. Most early "Trebles" appear to have been sent out with plates giving the voicing as "Normal", however, an indication perhaps that the Dispatch Dept. had not quite got the hang of the new type. Chassis were initially produced by Burndept.
A little way into production, voicing came to be designated clearly in the preamp (presumably for the benefit of assemblers on the work benches and the testers) - normally "TREBLE" stamped in red, and a flash of red paint for quick identification. See for instance serial numbers 10440, 10586, 10600, and 10705, which all have component date codes perfectly in line with the point of production in view - early 1964.
A detail of serial number 10600N (Treble).
A note on Burndept colour codes can be found on this page. A page on Westrex-made "Treble" chassis - which normally went into Super Twins - will be available shortly. A general overview of "Trebles", which will be updated periodically, is here.
Where component date codes are concerned, speakers consistently have the latest - i.e. later than any of those on the electronic components used in chassis. An overview of AC30s with dated speakers can be found on this page.
The page on AC30s with serial numbers in the 8000s, is here, and the page on serial numbers in the 9000s here.
If anyone knows of further AC30s that should be incorporated on this page, do let me know.
Updated
Serial number 10067 N (Treble) - currently in the UK
At present the lowest serial number known for a Treble chassis. Assembled by Burndept, chassis number 03417. The coupling caps are 0.047uf. The additional resistors and capacitors for Treble voicing can be made out at the volume pots. Woden transformers: choke with date code "KU" = October 1963, output with "MU" = December 1963, and mains with "AV" = January 1964. Thanks to Ben for the pictures.
Serial number 10081 B - currently in the UK
A Super Twin amplifier section. Chassis assembled by Westrex; Albion transformers; WIMA caps throughout the preamp.
Serial number 10082 N - currently in the UK
Chassis assembled by Burndept. Woden transformers with date codes "JU and "KU" = September and October 1963. Evidently very few changes in the preamp. The speakers have Pulsonic cones with code "41H1777". An overview of Pulsonic codes tabulated against Celestion date codes can be found on this page. Thanks to David for the pictures.
Serial number 10137 N - currently in the UK
Serial number 10140 - currently in the USA
Existence reported by Jim Elyea.
Serial number 10227 B - currently in the UK
Chassis assembled by Burndept. Woden transformers with "KU" date codes = September 1963. In the preamp, WIMA signal capacitors, a number since replaced with Mullard mustards. The "BASS" flag is still present on the front of the cabinet.
Serial number 10237 B - currently in Holland
Chassis assembled by Burndept. The Woden transformers have date codes: mains "MU" = December 1963; output "KU" = October '63; choke "LU" = November '63. The main Hunts preamp filter cap has date code "IUI" = 36th week of 1963. The main power amp filter cap has "TWI" = 41st week of 1963. The amp was exported to Holland early on, a Servaas (The Hague) affixed to the front.
A Super Twin amplifier section with a serial number in the 10300s also survives with a Servaas shop plaque.
Serial number 10261 B - currently in the UK
Sold on ebay in June 2006. Chassis assembled by Burndept. Described by the seller as having blue speakers, but the picture on the auction page showed a later silver.
Serial number 10309 N - currently in the UK
The serial number plate is now on a later AC30 (attached with non-standard screws).
Serial number 10317 N
Chassis assembled by Burndept; Woden transformers, output with date code "KU" = October 1963; mains "MU" = December 1963. WIMA capacitors in the preamp. Serviced by Alan Pyne, who took over 119 Dartford Road when Tom Jenning's new company - "Jennings Electronic Industries" - folded in 1975.
Below, a first set of pictures from 2022 (sale on ebay.uk)
THe same amp as above, but now with a black control panel, and pictured with a cabinet not present in the first set of photos. The date code of the Woden choke is "JU" = September 1963.
A third set of pictures from a subsequent sale of the chassis in the UK, 2022. The cabinet was sold separately.
Again, the same amp as in the two sets of images above. Original Hunts capacitors in the power section. The date code of the tone cut potentiometer is "KK" = November 1963. The EL84s were made in the Philips/Mullard factory in Ontario (Canada). In the preamp, English-made Brimar ECC83s and ECC82.
Serial number 10325 N - currently in the UK
Replaced grille cloth and painted vinyl, but still in good working order. Original Celestion T530s are present. The handles are of the type with plain rectangles in place of the normal Vox logo. These were used for a short time in 1964. Thanks to Bryan for the pictures.
Serial number 10348 N - currently in Australia
A beautifully clean standard AC30 Twin with integral top boost (controls in the main control panel). Note the presence too of the original cover. Transformers are Haddons (rather than Albions or Wodens). The chassis was assembled by Westrex. Note the presence of brown Dubilier resistors in the preamp. Further pictures are available here.
Serial number 10356 N - currently in the UK
Just the serial number plate with the shop plaque of Allan Billington. Sold on ebay, Nov. 2020.
Serial number 10380 N - currently in the USA
Still with brass vents. Number 10457, below, has the new style black.
Serial number 10427 N
Serial number plate removed from cabinet and sold separately on ebay.
NEW
Serial number 10440 N (Treble)
Chassis produced by Burndept, number 02901. Woden choke and mains transformer with "KU" = October 1963. Pots with date code "KK" = November 1963. Although the plate gives the voicing as "Normal", the chassis is in actual fact a "Treble". Thanks to Chris for the pictures.
Serial number 10457 - currently in Germany
Standard black "basketweave" covering. No integral top boost, so perhaps a substitute chassis. Original Celestion drivers in place.
Serial number 10459 - currently in the USA
Serial number 10471 - currently in Ireland
Further pics can be found here. Chassis assemebled by Westrex; Albion transformers. Original Celestion T900s still in place. In the preamp, WIMA red-print signal caps. The main preamp filter has the date code "UG" = July 1963. On the inspection tag, the amp is described as an "AC/36/X High Boost". The serial number is also recorded. Thanks to Alan for the pictures.
Serial number 10472 N - currently in the UK
Still part of the main AC30 numerical sequence, a Super Twin.
Serial number 10500 - currently in the USA
Existence reported by Jim Elyea.
Serial number 10556 B - currently in the UK
Serial number 10578 N - currently in the UK
Smooth vinyl. The chassis, assembled by Burndept, has top boost in panel. The date codes on the Woden mains and output transformers is "MU" = December 1963. The choke has "JU" = September '63.
Serial number 10586 N (Treble) - currently in the UK
Chassis number in the 3000s. Assembled by Burndept for JMI. Woden transformers with date codes: - mains "MU" = December 1963; output and choke "AV" - January 1964. The serial number plate gives the amp's voicing as "Normal" but the chassis is stamped "Treble". In the speaker compartment of the (well worn) cabinet, one Celestion blue and one silver. Pebble pattern vinyl covering.
Serial number 10600 N (Treble) - currently in the UK
Dark grey pebble pattern vinyl. On the back panel added Top Boost controls on a large black and white trafolyte panel, and a large VOX logo, also on black and white trafolyte. The handles, as is often the case at this point in production, have an empty panel, no VOX logo.
The speakers have the date code "16MH" = 16th December, 1963, for their manufacture. Cabinet, serial number plate, and speakers certainly belong together. A slight question mark surrounds the chassis (assembled for JMI by Burndept), which has Treble rather than Normal voicing. Possibly a mistake from factory, as 10586 above? Chassis number 2940. Woden mains and output transformers with "MU" = December 1963, choke with "JU" = September '63. Thanks to Robert for the pictures.
Serial number 10627 N - currently in the USA
Chassis made by Westrex; Albion transformers. At least one of the 25uf gold-coloured TCC capacitors in the preamp has the date code "UC" = March 1963. The original cathode bias resistor is dated "UE" = May 1963.
Serial number 10646 N
Serial number plate alone, sold in 2015.
Serial number 10672 N - currently in the USA
Pebble charcoal covering. Top boost in panel. Chassis assembled by Westrex; Albion transformers. The main preamp filter capacitor has the date code "UG" = August 1963. The original Celestion speakers (with "Heavy Duty" labels) are still in place.
NEW
Serial number 10705 N (Treble) - currently in the UK
Assembled by Burndept, chassis number 03450. In the preamp, one of the Hunts 25uf cathode bypass caps has the date code "TWI" = 41st week 1963 for its manufacture. The cabinet has been modified in various ways. Note the non-standard screws for the plate.
Serial number 10753 N - currently in the UK
A Super Twin amplifier section. Chassis assembled by Westrex, copper panel, top boost controls integrated. One of the gold-coloured TCC 25uf caps has the date code "UC" = March 1963. The underchassis is signed in pencil "DP" with an "X" in a circle (to denote "Expanded Frequency").
Serial number 10777 N - currently in the UK
A still from a clip of the amp on youtube.
Serial number 10900 - currently in the USA
Existence reported by Jim Elyea.
Serial number 10920 T - currently in the UK
Empty cabinet with serial number plate sold in the UK in 2024. The speakers from the cab had "29AJ" date codes - 29th January 1964 for their manufacture.
Serial number 10942 B - currently in the UK
Sold by a member of the Denney family. Chassis assembled by Burndept. Woden output and mains transformers have the date code "AV" = January 1964. The choke has something different - probably "BV" = February 1964. Covering smooth dark grey vinyl.
Serial number 10945 B - currently in the UK
Top Boost added on the back panel at factory. Pebble (dimpled) vinyl.
SERIAL NUMBERS UNKNOWN
Currently in Japan
Note the integral top boost controls in the copper panel.
Currently in the UK
Sold on ebay in January 2007. Integral top boost controls in the copper panel, as in the amp above.
Serial number unknown - currently in Japan
Top boost in panel.
Serial number unknown - currently in Japan
Chassis with top boost in panel assembled by Westrex; Albion transformers. On the underside, the standard marking "X", indicating "Expanded" or "Extended", initialled by "DP". The serial number plate (751xN) comes from another amp. The cabinet has basketweave vinyl and black vents.
Serial number unknown - currently in the UK
Chassis assembled by Westrex, top boost controls in panel, now in a cut-down Twin cabinet. Signed under chassis in pencil "DP" with an "X" (to indicate "expanded") in a circle. Transformers made by Albion. In the preamp, the gold-coloured TCC 25uf bypass capacitors (all three) have the date code "UF" - June 1963. The Vib-Trem volume pot may have a date code ending "L", which would be 1964, but the detail is too indistinct to be wholly certain. The original cement 50R cathode bias is still present in the power section. Sold by The Music Locker in 2022.