Blending amps is a terrific and easy way to maximize your tone and even increase volume. Live it’s impractical for those of us without roadies to carry more than two amps, but using multiple amps is something almost all of the big-name six-string stars do — from Angus Young’s four Marshall heads to Joe Bonamassa’s double-Marshall plus Diaz set-up to the improbable pig pile of Marshall and low-gain American amps that Stevie Ray Vaughan carried on the road for years. Correction: the pile of amps that Vaughan had his roadies carry for years.
On stage, it’s practical for most of us to simply double up, and playing through two small combo amps is a great way to get a big sound while keeping your back intact and not eating up too much stage floor space in small venues. Plus, if one amp fries you’ve always got a backup.
The first issue is getting your signal chain to feed two amps at once. This is easily solved. The most pro means is via a so-called A+B or Y box. The best of these are unpowered and simply work as a conduit for the signal chain. Place one after any stomp boxes you use and run cable cables from its two outputs into a pair of amps and you’re in business. But any tuner, like the popular Boss TU-3, or effects pedal with two outputs will also do.
Plus, running your signal out of a stomp box with stereo outs allows you to run your amps in stereo, verses two amps run in parallel mono. The advantage with stereo is that if you’re using a tremolo pedal or any kind of panning or delay unit with so-called “ping-pong” or sweep settings, you can get those effects to pass back and forth between the amps, upping the psychoacoustic intensity of your playing. For small rooms where you’re using stage volume to reach the crowd, this can be very controllable and effective. In larger spaces and when a sound engineer is involved, you’re at the engineer’s and sound system’s mercy. That said, even is a house mix runs only in mono it’ll still sound cool and inspiring on stage!
Another factor to consider is the amps themselves. The best ticket is combining amps with different sonic qualities so an entirely new and richer tone emerges when they’re blended. Think high-gain with low-gain, vintage with modern — opposites that form a new and attractive sound with double deployment. My favorite current rig includes a five-year old Epiphone Valve Standard combo with an Eminence speaker and a 1963 Vox Pacemaker, with the Epi set to bring out its delicious mids and high mids with just an edge of brights, and the Vox set to a low rumble to push the bottom end and low mids. Granted, that’s not what Voxes are typically known for, but the reverb-less and unpopular Pacemaker does this job extraordinarily well. And the blend is powerful and intoxicating.
In the studio, the number of amps you want to drive with a single guitar’s signal chain becomes a broad horizon, thanks to patch bays. The most amps I’ve driven for a single guitar part is five — a Marshall plexi, a Mesa-Boogie Dual Rectifier Tremo-Verb, a Supro Thunderbolt, a Twin-Reverb and a Vibro-Verb — along with a chorus, pitch shifter, Big Muff, Phase 90, wah-wah and my vintage Les Paul Standard to create a unique sonic wash for a textural rhythm bed as well as a feedback intro (sampled here) and outro. Of course, it’s easier to blend amps by plugging your guitar directly into the board and using a ProTools plug-in that allows you to select a variety of emulated amps and combine their sounds, but that’s not as much fun as really pushing air, and it doesn’t yield the same responsiveness for picking, feedback and other assets. A better-known example is Johnny Marr’s fantastic guitar sound for the Smith’s “How Soon Is Now,” where he and producer John Porter manipulated the tremolo on four Twins as the tape rolled. But the point is, using two or more amps at a time on stage or in the studio opens up a rich, new tonal palette. So double up, now!