Vox Amp Serial Numbers
Assuming the amplifier is all original, if the manufacturer's plate on the back of the amplifier says Jennings Musical Industries, that would date it before 1968. If the control panel is copper/red, that would be between 62-64. If the vents are brass, that would be earlier than mid 64. If black, that would date to mid 64-65.
The silver Celestions were introduced around 1965. If your speakers have not been reconed, you should see a manufacture date code on the gasket. Do you have any pictures to post? That would help.
Dating AC50s. Serial numbers, unfortunately, are not a wholly reliable means of dating early AC50s, that is to say, amps made from December 1963 to mid 1965. In large part, this is a result of production practice. Triumph Electronics, based in Purley in South London, made the chassis. These were then taken by road to.
Dating AC50s Serial numbers, unfortunately, are not a wholly reliable means of dating early AC50s, that is to say, amps made from December 1963 to mid 1965. In large part, this is a result of production practice., based in Purley in South London, made the chassis. These were then taken by road to Dartford, where back panels (with serial number plates) and boxes were supplied. In the process of loading, unloading and storing, any order that might have existed in the Triumph workshop was lost. There may be 'patterns' here and there, but nothing that one can rely on. An early Triumph chassis (serial no.
Control panels were sent by JMI to Purley for final assembly. The chassis, as mentioned, were then taken to Dartford, where the back panels were attached (the connectors soldered to the terminals in the amp), and the chassis screwed into the boxes that had been assigned. All is not lost however. One can often get a good general sense of date from the type of box, whether or not the amp has a valve rectifier, and last but not least, from the two-letter date codes on the potentiometers.
Serial number 1727. Some of the pots are replacements, but the one indicated is original and bears the code 'GL'.
'L' = 1964, and 'G' = July. The first letter is the month: 'A' = January, and so on. The second letter is the year: 'K' = 1963, 'L' = 1964, 'M' = 1965. Potentiometers were naturally bought in batches, each batch lasting several months.
But one nonetheless has a good terminus post quem ('date after which'). By early to mid 1965, Burndept Electronics, which shared a building with Vox off West Street in Erith,Kent, took over the bulk of production, and serial numbers consequently become more reliable as a means of dating - Burndept was a much more orderly place than Triumph. It should be said, however, that the Burndept chassis numbers stamped on the aluminium upright underneath the input jacks do not run in sequence with the serial numbers.
Early solid state rectified AC50 - only two main valves. There is no serial number plate on this amp, but the potentiometers are dated January 1965. Solid state rectification - the AC50 mark 3 with brimistor The brimistor - a type of temperature dependent resistor designed to delay in-rush current and voltage - was marked as addition on schematic OS/072 (14th October 1965), and first appears in amps around serial no. AC50 number 4133 has a brimistor, but no. 4282 does not. Download Lagu Ecoutez Aku Terbiasa Sendiri.
The transition took a little while.