Phasers are among the least understood of all effects, primarily because they’re often confused with chorus and flanging. This confusion isn’t helped one bit by the fact that one of rock’s most significant pedals - the Shin-ei Uni-Vibe - was billed as a chorus but in fact used a technique known as phase shifting.
Phasers work by duplicating the signal at the input, and sending one copy through one or more all-pass filters with a non-linear phase response. As you may know, if you play a signal against an out-of-phase copy of itself, they’ll cancel each other out. Here, though, they’re never precisely lined up, which results in peaks and notches across the frequency spectrum. More all-pass filters (or ‘stages’) mean more peaks and notches, and thus a more complex, interesting tone. The output may also be fed back into the all-pass filters, with some frequencies emphasised as a result.
The aforementioned Uni-Vibe was released under a number of names, among them the Jax Uni-Vibe-Chorus, and was tapped by luminaries such as Jimi Hendrix and David Gilmour.
The first rack-mountable phaser was Eventide’s Instant Phaser model PS 101. Released in 1971 for the price of $575, it was quite an exotic unit in its day, offering an internal LFO and a built-in envelope follower.
Now a well-known brand, MXR’s very first product was the Phase 90 pedal, a diminutive yet distinctive (and very orange!) slimline box with a single knob for controlling the speed of the phaser’s characteristic sweep. Introduced in 1974, it’s still in production today.
1974 also saw the release of the Electro-Harmonix Small Stone phaser, designed by Dave Cockerell of EMS Synthi fame. Here, the single Rate knob was joined by a switch that enabled the user to change the tone colour.
To read Computer Music’s full Vintage Effects feature, pick up the November 2018 edition.
Faux facsimiles of famous phasers
D16 Group Fazortan 2
If you’re in the market for some of that same sweet swirl that Jean-Michel Jarre used to wrap around his synths, you’ll be more than happy with D16’s far-out Fazortan. Modelled after two different hardware classics of yore, this sleek silver stunner offers dual LFOs with a choice of six waveforms, as well as multiple tempo sync options.
u-he know vintage sound, but they added all manner of modern touches to their phabulous phaser plugin, powered by an incredible 42 all-pass filters. A metallic modulation beast, one of Uhbik-P’s other best features is that it comes alongside eight other awesome plugins.
Audio Damage Phase Two
Audio Damage make the cut yet again with one of the best sounding retro phasers we’ve ever clapped ears on. Based on the highly-coveted Mu-Tron Bi-Phase pedal, this six-stage slab of blue swirl may look like and sound just like the real thing, but provides a bit more control thanks to its MIDI modulation options.
Can’t decide which old-timey phaser to get? Soundtoys think you shouldn’t have to choose. They’ve collected and modelled stacks of them to create PhaseMistress, a feature-stuffed phaser plugin that has even dedicated hardware heads singing its praises. From two to 24 stages, tempo sync and mind-blowing modulation - this is the bee’s knees.
Softube Fix Phaser
Paul Wolff is a highly-regarded designer of some of the most famous pro studio gear ever built. We’re talking API and Tonelux. He’s teamed up with Softube to produce a phaser with a decidedly retro sound. You want subtle? Fix Phaser will do it. You want the thickest jet engine sweep? Yeah, that too. Ten stages, three different swells.
You didn’t think we’d forget the freebie, did you? This one is a doozy, too. From smartelectronix and plugin legend Bram, this modulating tool features up to 23 stages, LFO and envelope control, and pre-phaser distortion or saturation. It’s been around for yonks, but it’s still just as good as some costly commercial offerings, all the same.