Electric guitarists often speak of the “Fender sound” or the “Marshall sound” when referring to amplifiers. And these amps certainly provide distinct coloration to the amplified signal, with different, but equally musical tones.

But bands leading the early British “invasion,” beginning with the Beatles, used other amps, the best known of which was the Vox. At various times Vox amps were used by The Animals, Rolling Stones, The Hollies, Manfred Mann, and the Dave Clark Five, among others. Many guitarists trying to emulate the Beatle’s heavy guitar tone on the Revolver album could never get that over-the-top sound on songs like “Taxman,” or “She Said,” or the dreamy “Tomorrow Never Knows” even when they used effects pedals. The secret to the sound is a cranked Vox AC-30 amp.

Vox amps were a collaboration beginning in the late ’50s between music store owner Tom Jennings and electronics guru Dick Denney. One of the secrets of the Vox AC-30 sound was its Class A design Denney incorporated (which basically means the amp runs full-up all the time, even when the volume is turned down). This yields a thick, crunching tone, but also makes the amp somewhat unstable and prone to failure. Another key to the AC-30’s distinct tone was the use of four EL-84 output tubes. The final part of the recipe was the use of two 12″ speakers. The early amps used Celestion G12s made exclusively for Vox and featured a blue-painted metal frame, which became the foundation for the legendary Vox Bulldog speaker used later.

An added feature came in the form of a “Top Boost” circuit, first incorporated in the early ’60s as a way to add brightness to the sound, and partially in response to Fender’s bright switch on its higher-output tolex-covered amps. This certainly gave the Vox AC-30 Top Boost, as it was known, an over-the-top sound. But while Vox was popular in England and Europe, the company never achieved its hope of deep penetration into the large U.S. market until it arranged with the Thomas Organ Company to distribute the line in America. What looked like a promising step was actually the beginning of the decline as amplifier circuit designs were changed, and the tone that originally defined the amp was lost. The AC-30 was as much a victim as the rest of the line.

Those seeking an original AC-30 must shop carefully, and with more than a little knowledge. The collectible AC-30s are somewhat rare and often difficult to distinguish from later versions. But there are some excellent resources available, including The Vox Story by David Peterson and Dick Denney (Bold Strummer, 1993). Fortunately, as part of the retro and reissue craze of the ’90s, the AC-30 has been reissued in its original design, with a sound very close to the highly soughtafter originals: the sound that makes the Vox AC-30 part of the VG Hall of Fame.