Echo Fix is an Australian maker best known for their tape echo units, so when they build an analog BBD chorus and vibrato, you expect them to understand modulation at a circuit level. The EF-P3 bears that out. It looks utilitarian: a plain enclosure, four knobs, a blinking rate LED, and two footswitches. But those four knobs give you more genuine control over the shape of the modulation than most chorus pedals twice the size.
Rate (far left, middle row) sets LFO speed, tracked by a blinking LED at center. Depth (far right) controls pitch swing width. Those are standard chorus parameters. The two knobs above them are what make the EF-P3 unusual.
Resonance (upper left) feeds the BBD output back into itself. At low settings it adds a flanging-type resonance to the modulation. Pushed further, it thickens the swirl until it sounds almost like a second pitch voice, even when the dry signal is muted.
Waveshape (upper right) morphs the LFO curve between sine and triangle waveforms. Sine is smooth and rounded. Triangle creates a punchier, spongier wobble with a more pronounced crest at each swing. It’s a continuous sweep, not a two-position switch.
The two footswitches handle bypass (right) and direct mute (left). The direct mute cuts the dry signal so the BBD output runs alone, putting you fully in vibrato territory. In the demo above I’ve set up sweeps for Resonance, Rate, Waveshape, and Depth, so you can hear each control in isolation.
The Spacey Chorus preset sets Depth at 10 with Rate at 0 and Resonance at 0, which gives you the widest, slowest chorus sweep the pedal can do, almost shimmery and barely moving. The Watery Chorus preset pulls Depth back to 3 but pushes Resonance to 10, and that combination produces a thicker, more resonant shimmer where the feedback adds harmonic density to the modulation.
Tape Vibrato (Resonance 4, Waveshape 8, Rate 2, Depth 6) is where the triangle waveform really earns its place. The more angular LFO gives the pitch swing a physical, tape-like quality, less like clean digital pitch modulation and more like something slightly mechanical and imperfect.
Ghostly Warble pushes Resonance to 9.5, Rate to 10, and Depth back to 2, and the result is fast and disorienting in a way that no standard chorus setting can touch. The high resonance feeding back at that speed creates an unstable, hovering quality, something between vibrato and ring modulation.
The Freqscene Effects Co. Koldwave is another analog BBD chorus-vibrato worth comparing directly. Both pedals go well past lush chorus into strange territory, but the routes differ. The EF-P3’s Waveshape control lets you shape the LFO curve itself, sine to triangle, while Resonance lets you tune the feedback character with real precision. The Koldwave’s equivalent trick is its Warp knob, which delays LFO regeneration to produce a looser, more physically erratic slipping sound. The EF-P3’s instability at high Resonance feels more intentional and controllable; the Koldwave’s Warp tends to feel less predictable in a way that suits weirder, more textural uses. The Koldwave also has a built-in clean boost stage, which the EF-P3 doesn’t.
This pedal makes the most sense for players who want to understand and shape their modulation rather than just pick a vibe from a few presets. The Waveshape and Resonance controls reward experimentation, and the Resonance sweep alone covers an unusually wide range from subtle and clean to harmonically dense. It works well in ambient, post-rock, and classic rock contexts, and the direct mute footswitch makes live vibrato switching practical. If you want something simpler to dial in quickly, a more conventional chorus with fewer parameters will get you there faster. If you want a BBD chorus that can go from a slow, wide shimmer all the way to something genuinely lo-fi and warped, the EF-P3 has the tools to get there.
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