One of the most satisfying developments of the boutique pedal age is the quality and attention to detail we see from the best small builders. Another benefit is the leeway for small-batch builders to play mad scientist and build for tastes and creative tendencies that fall outside the mainstream.


Thorpy delivers a tip-top quality phaser/vibrato that is both practical and experimentally aligned with the all-analog Pulse Doppler. Inspired in some measure by the UniVibe and David Gilmour’s custom-built Doppola rotary speaker, it’s a phase nerd’s dream—with functions for inverting phase notches, high-pass filtering, and an interactive control set that is complex, but which yields seemingly infinite micro-shades of phase. The merits of this deep functionality may elude casual one-knob phaser fans. But it will open up whole planes of possibility for detail-oriented sound sculptors, engineers, and producers, and players that relish the hunt for lush and off-kilter modulation tones.

Thorpy Pulse Doppler Review by premierguitar

All tracks are a Fender Telecaster through a black-panel Fender Tremolux and Universal Audio OX with tweed Deluxe and AC30 cabinet emulations. All modulation generated by Thorpy Pulse Doppler.

Control Freak

While there is appeal in a stupidly simple phaser, using one regularly tends to reveal the homogeneity in its modulation colors. The Pulse Doppler’s control set, however, is most certainly conceived to avoid sameness. Apart from the vibrato switch—which removes the dry signal—and the wet/dry blend, rate, and depth knobs, the controls are somewhat unorthodox.

The enhance control, which emphasizes resonant peaks by feeding phased signal back into the circuit, will be familiar to phaser users that have evolved beyond the caveman stage. But other controls take more time and practice to sort. The manual knob is the trickiest of these. In simple terms, it enables you to shift notch filter frequency emphasis. In practice, it’s much harder to pin down, and it can drastically affect output level and phase intensity, depending on where you situate the other controls. For most players, the noon position, which yields the fullest phase effects, will be the best place to start. But it’s illuminating to turn down the depth entirely and sweep through the manual control’s range to see how it shifts frequency emphasis. Once mastered, it can help sculpt unusual and mix-specific phase sounds.

Though the Thorpy can feel temperamental in the get-to-know-you stage, it’s easy to find varied and harmonically complex conventional phase textures.

The dual/figure 8 toggle is another source of mystery at first. In the figure 8 position, it inverts filter notches so they move in opposition to each other instead of in sync. At many manual settings, this results in a smoother, clearer phase sound that seems to foreground the dry signal. But at manual settings that emphasize higher frequency notches, that relationship is inverted, and this position yields more intense throbs.

The 3-position invert/pulse/normal switch yields more predictable results. At modest depth, blend, and rate settings, the invert position produces more syrupy and elastic phase textures that are both cohesive and trippy, while the normal setting creates harder, almost percussive pulses from within a more natural, full-spectrum voice. Thorpy attributes these differences to the straight and phase-shifted waveforms being in phase in normal mode and out of phase in inverted mode. The pulse position, meanwhile, acts as a high-pass filter, yielding highly focused modulations that can be fashioned into intense tremolo-like textures—particularly at high depth and wet blend settings.

Though the Thorpy can feel temperamental in the get-to-know-you stage, it’s still easy to find varied and harmonically complex conventional phase textures. But because the controls all have very wide range, it’s important to start with conservative settings. And exploring the wet/dry blend, feedback, and depth controls within the lower half or lower third of their ranges reveals many deep, immersive, and familiar phase tones.

The Verdict

The Pulse Doppler is an extremely powerful phase tool. Once you master its highly interactive and sensitive controls and get a feel for its more unconventional functionality, the possible tones, musical applications, and creative prompts become myriad and thrilling. If you intend to use the Pulse Doppler in a live context, you’ll want to put in the time to learn it backward and forward. Very small alterations to the highly sensitive controls can shift the phase texture drastically. And without preset capabilities, you’ll need to mark your favorite settings very carefully or have a pretty precise and unfailing memory. The upside is that all this range means that you can readily move from deep, liquid variations of familiar phase tones to intense and weird modulation colors that can make a pedestrian riff unforgettable. Gigging players may want to seek simpler solutions, but as a creative studio tool, the Pulse Doppler is a phaser with few rivals.

From Your Site Articles

Related Articles Around the Web

Audio Premier Guitar