Vox AC100 no. 531
AC100 serial number 531, an early "100W Amplifier", produced around July 1965 and exported to the USA early on, as many of these AC100s were.
Three of the original yellow-print Mullard XF2 EL34s survive, date codes B5C5, B5E4 and B5E5 = Blackburn Factory, 5th week of March 1965, and fourth and fifth weeks of May '65. The fourth valve is an American GE-branded XF2, date code B5H3 - perhaps a replacement for a broken original soon after the amp had arrived in the States.
For the moment, pictures of the exterior and the cover. Interior shots to follow.
For related amps, see the main "100W Amplifier" page.