Home » Recording Resources » Featured Reviews » July 2023: Strymon Zelzah Multidimensional Phaser

Two phasers is better than one

Review by Paul Vnuk Jr.

Today we are checking out the Zelzah Multidimensional Phaser pedal from Strymon. Zelzah is two phasers in one and offers a broad palette of modulation colors far beyond a typical phaser pedal.


What Zelzah Is

Zelzah is housed in a midsized 4.5″ (D) x 4″ (W) x 1.75″ (T) Strymon enclosure with a 6-knob, 2-toggle, 2-stomp switch configuration similar to El Capistan V2, DIG V2, Deco V2 and Blue Sky V2. Zelzah comes in metallic purple (the coolest Strymon finish ever), or a Midnight Edition black while supplies last.

Strymon Zelzah pedal close upConnections

On the back of the pedal are four 1/4” jacks (In, Out L, Out R and EXP/MIDI). Zelzah can operate as mono > mono (left output), mono > stereo, stereo > stereo, or even as two dual-mono pedals. Stereo input requires the use of a TRS-Y cable. A mono-stereo input switch selects the input mode.

Also on the back of the pedal is a USB C jack and a 9V DC input for use with the included 9V power adapter.


Like all Strymon V2 offerings, Zelzah offers MIDI implementation for firmware updates and parameter control. In addition to USB C, the expression pedal socket can be used with compatible 1/4” MIDI devices, including the Strymon Conduit TRS & MIDI Hub ($149), reviewed in November 2021.

Strymon Zelzah pedal - backWhat Zelzah Does 

Zelzah features two fully independent 6-Stage and 4-Stage phasers. The pedal can run in Series (default), Parallel (both in stereo) or Split mode, which splits each phaser to the individual left and right outputs in mono.

The 6-Stage phaser is on the right and runs into the 4-Stage on the left when in Series, and each has its own stomp switch, three knobs and a function toggle.

Combination button presses and dial turns adjust the “under the hood” Live Edit Functions. These include signal routing, stereo width, phase polarity, LFO MIDI clock sync, input levels, expression, bypass mode (buffered or true) and more—it’s pretty extensive, so check out the manual.

The 6-Stage Phaser

The 6-Stage phaser begins with Resonance choices of off, mild and strong. Think of these like the resonance parameter on a synth filter. Each one alters the sound of the phase effect from warm and mellow to intense and cutting. That said, Zelzah maintains a rich warmth throughout, never becoming overly biting or harsh.

Next up is a pair of phaser pedal standard Speed and Depth knobs. These adjust how fast and big are the peaks and dips of the LFO—basically, how much you notice the sweep and pulse of the modulation. In some operating modes, the red signal LEDs above both stomp switches pulse in time with the LFO speed.

Lastly, the Voice knob changes the modulation style from a classic sweeping phaser when fully counterclockwise to a flanger at 12 o‘clock and a chorus fully clockwise. That may sound simple, but while the pot is not stepped, Strymon let me know that it is controlling 30 parameters under the hood, and every degree of the knob’s travel was curated to offer something different. In other words, make sure to explore every turn of the dial.

The 4-Stage Phaser

The 4-Stage is your classic 70s-style pedal phaser—think guitar and electric piano. The 4-Stage offers three settings: classic, barber and env.

Classic is what it says on the tin—the phase sound you know and love.

Barber refers to how the red and white candy cane-style lines swirl around a vintage barber pole. Here it means the sound of the phase sweep continues to cycle and rise (or fall) rather than a typical up-down motion. Different from many Shepard Tone/barber pole style offerings, Zezah uses three 4-stage phasers running concurrently to produce those sounds. This setting can be fine-tuned in Live Edit mode.

Env invokes an envelope-style phase response reminiscent of an auto-wah or an envelope follower pedal. The phase is triggered and responds to the pedal‘s parameter in response to the attack and intensity of the source signal.

Lastly, there are Speed and Depth controls and a Mix knob. Since the 4-Stage phaser does not offer any intensity settings, the Mix control helps you lessen or exaggerate the effects of the phase, and it is very helpful when used with the env option.

Getting Your Phase On and Off and On and…

I tried Zelzah on analog synths, Fender Rhodes, as an effect send and return in my DAW (great for adding vintage phase sweeps to drum fills), and while I am not a guitar player, I did have it set up in some recent guitar tracking sessions.

On guitar, even in mono, Zelzah runs the gamut from classic late 60s/early 70s psychedelic whisps and washes with the 4-Stage to some great 80s and 90s era flange, chorus and vibrato tones with the 6-Stage. The envelope mode may be my favorite, ranging from a subtle bulbous grab to a full-on „wonk and wah.“ It was even nicer when fed with mild to strong phase tones from the 6-Stage. It‘s also possible to get some great “talk-box“ and vocal formant-style sounds with strong settings on the 6-Stage, which can again be finessed in cool ways with the 4-Stage envelope.

On Rhodes piano, while it can certainly do the “phase 90“ thing, what I liked even more, was that it was quick and painless to make my mono electric piano swish in stereo. This was similar with the mono out of my Moog Voyager, and especially my mono-only Sequential Prophet-5.

On the 6-Stage side, at the slowest speed, Resonance off and Voice on phase, you can coax out a slightly fast, driven ring mod style attack—like a metallic robotic sheen to the onset of notes. On the 4-Stage side on synths, the ever-climbing barber effect was a great addition to slow-evolving otherworldly pads. The envelope setting works nicely on slow, long attack sources, adding an almost slow-growing filter effect.

Routed in your DAW as an outboard send-return effect, as with my review of the Cloudburst pedal (May 2023), it‘s great fun to use MIDI over USB C to automate parameters and play the pedal as a synth. Crafting evolving, evocative textures can be fun as you finesse the settings in real-time.

Crushin‘ On Zelzah

The Strymon Zelzah is so much more than your typical phaser pedal. Zelzah is very much a phasy-swishy-flangy-chorusing multi-effect of the highest order. Not just because it is two phasers in one, but because of the broad throw of modulation flavors and routing flexibility packed in its sexy purple exterior—yes, I recommend the purple.


Price: $349

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