Bass History
Origins of the Iconic Ampeg SVT
Moments in Bass History: Origins of the Iconic Ampeg SVT
Tim Fletcher delves into the origins of the iconic Ampeg SVT; “the biggest, nastiest bass amplifier the world had ever seen”, and how The Rolling Stones accidentally became the first endorsees.
By the last concert of their 1966 US stadium tour, at the Candlestick Park baseball stadium in San Francisco, The Beatles had decided to stop playing live*. Their 100-watt Vox amplifiers, and the house PA system – normally used for announcements rather than projecting the sound of a band – were not powerful enough to be heard over the screaming of the 25,000 crowd members. Without monitors, the band couldn’t hear themselves sing, and Ringo couldn’t hear the rest of the band; he had to rely on watching their ‘wiggling backsides’ to stay in time with them. The band had been unhappy with the quality of their live performances for a while, and after this show, they finally decided to focus purely on studio recording. However, the Beatles had set a precedent, and the move towards stadium gigs had begun.
To accommodate the need for more onstage volume, amplification companies began to build bigger and more powerful guitar amps; by the late 1960s, Fender had raised the output of their Twin model to 100w, and Hiwatt and Marshall had produced 200w heads. Bass amplifiers had also become more powerful; Sunn had developed their 150w Model T, and Acoustic had unveiled their 200w 360 model.
Not wishing to be outdone, over at Ampeg, Bill Hughes and Roger Cox were designing “the biggest, nastiest bass amplifier the world had ever seen”, an all-tube amplifier they named the ‘Super Vacuum Tube’ or SVT for short.
The amp utilized fourteen tubes, and produced a massive (for the time) 300 watts at 8 ohms. It was designed to run through two 8×10 speaker cabinets to get the maximum output, although later speaker enclosures were uprated to enable the head to run through one cabinet. It was so loud that the designers warned users that; “THIS AMP IS CAPABLE OF DELIVERING SOUND PRESSURE LEVELS THAT MAY CAUSE PERMANENT HEARING DAMAGE”. The SVT prototypes were unveiled at the NAMM show in Chicago in late June 1969, but they didn’t go into production immediately.
In October 1969, the Rolling Stones arrived in the US to begin their much-anticipated tour.
After a three-year absence, the band wanted to play to larger audiences and they booked stadium venues such as the LA Forum, Madison Square Gardens, and the Detroit Olympia. They also agreed to play a free outdoor concert in San Francisco (later moved to the Altamont Speedway) before returning to the UK. The Stones began their rehearsals for the tour in Steven Stills’ basement in Laurel Canyon, Los Angeles, but soon moved to a larger sound stage at the Warner Brothers’ studios in Hollywood.
The band had shipped their Fender amplifiers to the US for the tour, but their roadie had forgotten about the voltage difference between the UK and the USA, and very quickly, the amps were fried.
Stones road manager and keyboardist Ian Stewart got in touch with Rich Mandella at the Ampeg office in Hollywood, who quickly gathered five of the SVT prototypes and headed down to the rehearsal. To his surprise, it wasn’t just Stones bass player Bill Wyman who took an SVT; guitarists Keith Richards and Mick Taylor also chose to use them. Richards cranked the amps to the point of meltdown, and Mandella had to keep swapping out the amps to let them cool off. However, the band loved the amps, and Mandella was hired to act as the tour’s backline technician. The SVTs can be seen in many photographs taken on the tour, and also in the Maysles brothers’ film ‘Gimme Shelter’, especially in the footage shot at the infamous Altamont concert.
The SVT went into production in early 1970, and it has been the amplifier of choice for many bass players in the decades since, including Robert Trujillo, Cliff Williams Krist Novoselic and Sting.
The company continues to make SVT models today, including the 1000w SVT-7 pro. The SVT is still seen as the ‘reference amp’ for live rock bass amplification, and former Bass Player editor Scott Malandrone commented that; “The SVT has done for the sound of electric bass what the Marshall Super Lead had done for the electric guitar – it would give the instrument an identity”.
*Interestingly, the last artist to perform at Candlestick Park was Paul McCartney who played there 2014, after which it was demolished.

Above: Richards and Wyman in front of their SVTs at the fateful Altamont concert. Photo Credit: Beth Bagby

Above: Wyman with the Stones on a later tour. Photo Credit: Tony Barnard