Vox AC30: copper and grey panels, Celestion silvers
Later 1964: serial numbers in the 16000s
Serial number 16337 TB, amp model and number machine stamped, voicing (TB = Top Boost) hand-stamped.
Continued from the page on AC30s with serial numbers in the 15000s. So far no Super Twins with stray numbers in the 16000s have come to light.
Grille cloth remains brown.
One finds four models: the "Treble", designated with a "T" on its serial number plate; "TB" for "Top Boost", normally with the circuit's controls integral in the control panel; "N" for "Normal" voicing, and "B" for Bass. The three last had their own schematics, in order: OS/056, OS/065 and OS/057. Some notes on the treble circuit, which was new in 1964, can be found on this page.
A growing collection of documents relating to the AC30 in 1964 can be found here.
Significant component date codes in amps on this page are mostly of later 1964: second and third quarters of '64 ("B/64", "B4N" and "C4N") for Mullard "mustard" caps; and "HV" = August 1964 for Woden transformers.
Transformers are Albions, Parmekos, and the new Wodens (with a simplified internal construction) - see this page.
Celestion silver alnicos - the T1088 - designed for JMI in the Spring of 1964 are now the norm. Amps with serial numbers in the 15000s occasionally still have blues. The earliest date codes known for Celestion silvers are from the middle of May.
Grey control panels, which are also to be found sporadically on amps with numbers in 12000s-13000s, are pretty well the norm too. For an exception, see serial number 16649, below.
As mentioned at the head of this page, serial number plates are normally machine stamped. The voicing - "N", "T" or "B" - is still hand stamped, however.
If anyone knows of further amps that should be incorporated on this page, do let me know.
Serial number 16041 B - currently in the UK
Chassis number 8128. Grey panel, silver Celestions. Parmeko transformers. The Mullard mustard capacitors have the date code "B/64" = second quarter of 1964. The blue Hunts cathode bypass caps have "HIT" = 21st week of '64 (last week of May). The footswitch is of the old circular type. A good well-used AC30. Its grille cloth has been renewed with brown Rose Morris cloth. Thanks to Danny for the pictures.
Serial number 16169 TB - currently in Sweden
Grey control panel, integral top boost. Cabinet re-covered in red - the speakers are new Celestion blues.
Serial number 16337 TB - currently in the UK
Excellent condition. Grey control panel, integral top boost. The speakers are Celestion silvers (T1088).
Serial number 16500 - currently in the USA
Existence recorded by Jim Elyea
Serial number 16541 - currently in Sweden
No pictures at present, but some notes on components: Woden choke date code "HV" = August 1964; Mullard mustard capacitors in the preamp "B4N" and "C4N" = second and third quarter of 1964; and Hunts capacitors "HWT" and "IYT" = 21st and 30th weeks of '64.
Serial number 16649 T - currently in Europe
Chassis number 8001. Copper panel. Celestion silvers. The Mullard mustard capacitors have date codes "B/64", B4N" and "C4N" = second and third quarters of 1964. The Woden output transformer has the date code "HV" = August 1964.
Serial number 16965 - currently in the UK
Grey panel non-Top Boost. Celestion silvers.
Serial number 16983 T - currently in the UK
Sold on ebay some time ago.