Seymour Duncan SFX-07 Shape Shifter

IN THE LATE Forties when DeArmond introduced the Trem-Trol, the world’s first stand-alone effect for electric guitar, this portable tremolo device shook the world. (Actually, it shook a tiny canister filled with electrolytic fluid to create its trippy n/off effect.) In the Fifties and Sixties, amplifier builders created electronic circuits that duplicated this mechanical effect and slapped them into their amps. In the Seventies the first electronic tremolo effect pedals started to appear, and since then more than 200 models have made their way to market. With so many options already available, why would anyone in their right mind bring another tremolo effect pedal into an already crowded marketplace? The answer is that Seymour Duncan believes it has a better idea with its new SFX-07 Shape Shifter tremolo pedal, The SFX-07 has just about every feature you could want from a tremolo unit, and a few new ones. If you have a particular tremolo sound in mind, chances are pretty good that the Shape Shifter can create it along with ones you’ve never imagined before.

MOST TREMOLO PEDALS offer little more than rate and depth controls and—if you’re lucky—a switch that lets you select triangle/sine or square wave patterns. The Shape Shifter has the requisite rate and depth controls, but it also boasts a Wave control that continuously morphs the wave shape from sine to triangle to square, a unique Shape control that lets you vary how quickly the effect’s volume increases and decreases, and a tap tempo footswitch that lets you tap in tremolo rates that are perfectly in synch with a song’s tempo. The rate control functions as a four-setting tap ratio selector when the rate/ratio switch is set to the ratio setting (confirmed by a red LED on the front panel). The 1:1, 2:1, 3:1 and 4:1 settings generate quarter, eighth, triplet and 16th-note tremolo effects, respectively, and you can manually switch between ratios while remaining perfectly in synch without having to re-tap the downbeat. A yellow LED pulses in time with each tremolo “beat” so you can visually monitor the rate as well. The Shape Shifter has a mono input and a mono output. If you want stereo Seymour Duncan SFX-07 Shape Shifter tremolo pedal panning tremolo you’ll have to look elsewhere. It’s housed in a bulletproof 16-gauge steel chassis and operates on a nine-volt battery or with an optional AC adapter. The signal path is 100 percent analog (with true bypass), and its internal digital processor controls only the tap tempo function.

WHETHER YOU WANT smooth vintage amp-style tremolo (sine wave) or more modern, choppy helicopter effects (square wave), the Shape Shifter does it all. The rate ranges from 1 to 20 cycles per second, which maxes out in a stuttering warble that’s about as fast as the human ear can perceive. The effect produces warm, noise-free tones that preserve the fullness of your guitar’s original signal. The SFX-07’s unique effects lurk within its shape control settings. At the center 12 o’clock setting, the SFX-07 operates like all those other tremolo effects you know and love, but when you dial the shape control to the left, the effect rises in volume more quickly and fades more slowly. When you dial the control to the right, the opposite happens—the effect rises in volume more slowly and fades quickly. Turn the control all the way to the left and the guitar’s attack becomes very percussive and aggressive, while at the rightmost setting the effect sounds similar to a backward recording. The tap tempo function works very well once you’ve gotten used to the “action” of how the footswitch clicks, and it’s easy to nail the perfect tempo every time. The ability to switch ratios from quarter notes to eighths, 16ths or triplets without missing a beat provides numerous creative options to explore, especially if use the Shape Shifter with a device like the T.I.P. Third Hand, which will let you adjust the ratio control with your foot.

THE BOTTOM LINE WITHOUT A DOUBT, the SFX-07 is the most versatile tremolo pedal in its price range available today. If you want to emulate the classic tremolo effects of vintage amps that are priced well beyond your budget, explore modern textures and new effects or all of the above, the Shape Shifter is a great choice whether you’re looking for your first tremolo pedal or the last one you’ll ever need.

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Chris Gill

Chris is the co-author of Eruption - Conversations with Eddie Van Halen. He is a 40-year music industry veteran who started at Boardwalk Entertainment (Joan Jett, Night Ranger) and Roland US before becoming a guitar journalist in 1991. He has interviewed more than 600 artists, written more than 1,400 product reviews and contributed to Jeff Beck’s Beck 01: Hot Rods and Rock & Roll and Eric Clapton’s Six String Stories.