AC30 Super Twin amplifier section serial number 12563 serving as a PA amplifier with two LS40 speaker columns.

AC30 Super Twin amplifier sections twinned with Line Source columns - for Public Address purposes - were surprisingly popular in the 1960s. A good number can be traced in the small ads placed in "Exchange and Mart" and "Melody Maker" magazines in the mid and later 1960s. Some of those entries will be posted below.

The material being assembled on this page will eventually be dovetailed with the existing page on Vox 30 watt Public Address amplifiers.

The JMI column speaker instruction sheets

A detail from the instruction sheet supplied by JMI with its Line Source 40 column speakers showing the requisite connections at the speaker terminal blocks of Vox amplifiers.

AC30s are generally fairly consistent in the arrangement of their 8ohm and 16ohm taps, conforming in the main to the order given in the schemas, the only inconsistency being the colours of the leads issuing from the transformers - brown (8 ohms), black (comm), green (16 ohms) for some earlier Wodens; green (8 ohms), black (comm), blue (16 ohms) for Albions and other Wodens.

Early AC80/100s and AC50s are a case apart. The common in the former was generally the lowest terminal of the three. AC50s often had common at top. But as XLR speaker sockets were generally standard on the back panels of these amps, the relative order of connections did not matter just so long as they were correct in relation to those on the socket.

AC30 Super Twin IIs and Super Reverb Twin IIs normally also had XLR sockets on their back panels.

Detail of an AC30 Public Address set from late 1963 / early 1964 - Super Twin amplifier section, two LS40 speaker cabinets - still with its original cables. Two ends have XLR sockets to plug into the speakers, the other two have bare wires screwed into the 8 ohm tap of the amplifier's terminal block, as illustrated in the guide above: "Two in parallel at 15 ohms each".

Back to the Vox AC30 Super Twin index page