The amps on this page, all valve rectified, were assembled for Vox by Triumph Electronics in Purley in the second half of 1964. For more on Triumph, see this page.
Serial numbers, as mentioned on the previous page, are not a reliable guide to relative date. Finished chassis, boxes and serial plates were brought together in a fairly random way by Triumph.
Unlike the AC50s made later on at the Burndept factory in Erith, Triumph-made amps do not have numbers stamped on the flat of the aluminium chassis underneath the input jacks..
Two new-style voltage selectors come in (the old type of selector had a removable plug). First, a selector with a slot in it (probably the width of an old penny) as found also in certain AC10s. This was eventually superceded by the more conventional dome voltage selector.
The feeling is that Triumph used up its box of slot selectors first - perhaps 50 or so - and then moved on to the new boxes of dome selectors.
Most of the details noted on the previous page hold good for the amps pictured below, with one principal exception: speaker output sockets are now rectangular Cannon XLRs rather than 1/4" jack.
Mains cables are still hard wired - there is no socket on the back panel.
Shelf-mounted reverb units (factory-fitted) occasionally occur.
Serial numbers were hand-stamped up to and presumably a little beyond serial number 1746. Machine-stamped numbers come in at some point before number 1763.
The pencil signatures of the checkers who signed the AC50s off can regularly be seen on the underside of chassis - "DE" is Dave Earp, who worked for the company in the mid 1960s. "K" at present is unknown. The checked bias voltage was also noted in pencil.
In terms of speaker cabs, AC50 no. 1607 below (dome voltage selector) has its original 2 x 12" enclosure for guitar (containing two Celestion alnico T1088s sprayed silver/poly grey and one Midax horn). A good number of amps figure with Foundation Bass cabs - probably the ones with which they were originally paired.
Below, a register of amps. If anyone knows of others that have not yet been included, do let me know.
Serial number 1462 - currently in the UK
Sold on ebay.uk in April 2012. Replaced grille cloth. Hand-stamped serial number. Seller noted that the outputs were jack sockets rather than XLRs.
Serial number unknown - whereabouts unknown
Black escutcheon panel for the XLR sockets.
Serial number unknown - whereabouts unknown
Original XLR connectors in place on an early-style black plate. Note that no mains connector was provided - the lead is hard wired, as in the case of no. 1678 below. Also note that the fixing on the top edge of the back panel is centred.
Serial number unknown - currently in the USA?
Probably to be included here - new grille cloth, but otherwise all there. Note the old-style black panel for the output XLRs. The cab and trolley may be later however - observe the round Amphenol connector. Early cabs had rectangular Cannons. See this page.
Serial number 1727 - currently in the UK
Sold on ebay.uk in Jan. 2013. Good overall condition; replaced handle. The output plate is new-style (ie. not the early black type); white warning plaque; slot rotary selector. Hand-stamped serial number. One of the pots has the code "GL" = July 1964. Note that serial number 1725 has the newer domed voltage selector.
Serial number 1729 - currently in the UK
Missing its voltage selector. Serial number plate fully hand stamped. The latest discernible date code in the preamp is "A4N" on one of the mustard caps = 1st quarter of 1964. But the amp is likely to have been made in the third quarter of the year.
Serial number 1766 - currently in the USA?
Mains lead hard wired. Original XLR output sockets in place. Possibly a slot voltage selector, though hard to be absolutely sure from the small pictures from ebay.
Serial number 1800 - currently in the UK
Sold on ebay in late 2014. Accompanied by a solid state Foundation Bass cab. Hand stamped "AC50"; machine-stamped serial number.
Serial number 1847 - currently in Japan
1/4 inch jack sockets instead of XLR connectors - apparently original. Note that an amp on the previous page (with a link voltage selector) has an output panel of the same sort (white circular surrounds for the jack sockets). Machine-stamped serial number. Images originally posted here.
Serial number unknown - currently in New Zealand
Grille cloth and baffle replaced, but to judge from the control panel, in good condition otherwise. Transformers look to be original.
For small-box amplifiers with grey panels and dome voltage selectors. See this page.
Serial number 1499 - currently in the UK
Sold on ebay.uk summer 2014. Replaced grille cloth and escutcheon plate.
Serial number 1578 - currently in the UK
Produced in late 1964. Electrolytic caps replaced, and some resistors here and there, but in good overall condition. Serial number plate fully hand stamped. For further pics, click on the links below.
Serial number 1594 - currently in the UK?
A replaced output transformer, but otherwise in reasonable condition. Hand-stamped serial number.
Serial number 1607 - currently in the UK?
A nice amp and cab, the cab with early silver Celestion T1088s (note the profile of the dust cover).
Serial number 1678 - currently in the UK?
Sold on ebay uk, November 2012. Mustard caps date to the second quarter of 1964 (B/64). Note that the mains lead is hard-wired (original).
Serial number 1686 - currently in Germany
Hand-stamped serial number plate. Thanks to Heinz for the pictures.
Further pictures, paired with a solid state Foundation Bass cab.
Serial number 1709 - currently in the UK
Grille cloth on both amp and cab replaced, but otherwise all good. Hand-stamped serial number.
Serial number 1720 - currently in the USA?
Replaced voltage selector. Hand-stamped serial number. The preamp looks pretty much untouched. Pictures originally posted here.
Serial number 1725 - currently in the USA?
Mains lead hard wired. Hand-stamped serial number. Sold on ebay in 2011.
Serial number 1740 (box only, later amp inside) - currently in the UK
A nice Foundation Bass set - the cab in particularly fine condition. The amp cabinet may have been recovered in old cloth to match. The AC50 is solid state and later - ie. it has been reboxed in the box that originally belonged to serial number 1740, now gone.
Serial number 1743 - currently in the USA
The amp has been regrilled, but the cloth on the cab, which is in excellent condition along with its roller trolley, is original.
Serial number 1746 - currently in the UK
Voltage selector replaced / modified. The original OT is gone but the amp is in reasonable condition otherwise - only a few changes in the preamp. The cover - in green drab (?) is the one issued with the unit in 1964.
Serial number 1763 - currently in the UK
Mains transformer replaced and logo probably from its Foundation Bass cab. The preamp is more or less untouched. The 0.1uf mustard caps have the date code B/64 = second quarter of 1964. Voltage selector gone.
From this point serial numbers are machine-stamped (rather than hand-stamped) on the plates
Serial number 1775 (?) - currently in Canada
A highly-polished AC50. Hand-stamped serial number. A couple of ancillary speaker output jacks added on the escutcheon plate.
Serial number 1786 - currently in the UK
A replaced choke, but otherwise in excellent condition. Note that batches of AC50s, including this one, have rectangular silver mica signal caps, probably Lemcos (up by the tone controls).
Serial number 1796 - currently in the UK
Voltage selector removed. The amp designation "AC50" is hand-stamped on the plate; the serial number itself machine-stamped.
Serial number 1815 - currently in the UK
Great condition. The preamp is entirely untouched. Original mains lead (hard-wired) still in place.
Serial number 1821 - currently in the UK
Serial number 1855 - currently in the USA
Evidently in good condition.
Serial number 1999 - currently in the USA
Paired with a US Vox cab (Berkeley).
Serial number 2031 - currently in the UK
Late 1964. Note that V O X is in individual letters on the amp, as no. 1999 above, and no. 2069 below. The cab is late JMI, from 1967. Thanks to Dave for the pictures and info.
Serial number 2069 - currently in Australia
Brown grille cloth. Individual letters for the logo V O X. The underchassis is signed "DE" = Dave Earp who worked at Triumph in the mid 1960s. The transformers have paper stickers with their codes: mains is JMI M 007A; output is JMI D 008A; and choke is JMI X 009A. Thanks to Glen Lambert for the pictures.
Serial number 2072 - currently in Italy
As above, individual letters for the logo; but black grille cloth. Replaced mains and probably output transformers. Pot codes are JL = October 1964. The same blue Hunts capacitors as in the amps above. Sold on ebay in mid 2012.
Serial number 2143 - currently in the UK
Serial number 2147 - currently in the UK
Single letters for the V O X logo as in the amp below. Distinctive Triumph transformers visible through the top grille.
Serial number 2164 - currently in Sweden
A few changed components here and there, but otherwise good. The amp belonged in the 1960s to the bass player of the Swedish band The Sleepstones. Thanks to Lenny for the pictures.
Serial number 2172 - currently in Europe
"AC50" still hand-stamped on the plate.
Serial number 21xx - currently in the USA?
Single letters - V O X - for the logo, as in the case of a number of amps on this page. Voltage selector unfortunately missing. Black escutcheon panel for the XLR outputs.
Serial number unknown - currently in the UK
Mains cable still hard-wired. Pictures from this page.
Serial number unknown - currently in the USA
Pot codes "GL" = July 1964, so the amp probably produced late 1964. The box, with its Amphenol connectors, is later.