AC/DC guitar tech Trace Foster explains why Angus Young’s live sound requires no fewer than 12 Marshall stacks

Angus Young and Trace Foster
(Image credit: Brian Rasic/WireImage; Twitter)

AC/DC’s electric guitar tone is famously one of the most unfussy sounds in rock ’n’ roll. There is no pedalboard to worry about. Angus Young just needs a Gibson SG brought to pitch, a guitar wireless system to give him free run of the stage, and cranked Marshall. Sounds simple.

But veteran tech Trace Foster has revealed that getting this sound onstage is tougher than it seems. In a recent interview with Ultimate Guitar, Foster explains that massive stage volume is needed to get Young’s sound to behave the way he needs it, and in the stadium shows and outdoor environments in which AC/DC play, where the weather plays its part, he requires no fewer than 12 Marshall stacks to get his sound each night.

“People don't understand that, for example, if it’s cold out, sound does not travel,” said Foster. “It will travel about three feet in front of the speaker and just die. When you have a guy who doesn't wear in-ear monitors and he relies upon sustain, well now that's a huge problem because you can't give him that thing he needs and you’re struggling.”

Luckily, Foster, who has worked with the likes of Joe Perry, Melissa Etheridge and Cheap Trick, has an on-site guitar amp tech, Simon Murton to work with, and before each show, Murton will bias each amp while Foster plays Young’s guitar through them. The only certainty is that over time there are going to be casualties mid-show and the other amps will have to pick up the slack.

“We push those amps way beyond where they should ever be pushed,” explained Foster. “We know damn well we're going to blow a few up now and then, but it doesn't matter. I have to be able to sustain a note at certain spots on that stage and it takes all 12 of those amps to make that happen.”

Foster says that AC/DC are 100 per cent old-school. Guitarists looking to replicate this sound at home should not look to digital amp modellers or high-tech solutions to what is essentially an act of rock primitivism. 

Recent years have drawn attention to the significance of the Schaffer-Vega wireless system in the mix, which Angus – and others – historically used even in the studio; it had a receiver tower with a clean boost that could push the amp. SoloDallas even brought out a replica of the hard-to-find wireless system’s boost circuit and put it in a pedal, the Schaffer Replica Storm.

Foster, however, says the secret is more straightforward, and there is no single overdrive pedal that will do the job. “The thing with AC/DC, in general, their tone is really clean and clear, the tone comes from sheer volume,” said Foster. “To get Angus' tone, and you turn it up all the way until the speaker completely exerts itself, meaning the cone moves forward but can't move back, then you back it off to where it's got movement again. That's where that sound comes from.”

Thereafter you are instructed to hit those strings as hard as you can and make the amp fight back. Check out the full interview over at Ultimate Guitar

Jonathan Horsley

Jonathan Horsley has been writing about guitars and guitar culture since 2005, playing them since 1990, and regularly contributes to MusicRadar, Total Guitar and Guitar World. He uses Jazz III nylon picks, 10s during the week, 9s at the weekend, and shamefully still struggles with rhythm figure one of Van Halen’s Panama.