The Freqscene Effects Co. Koldwave is a fully analog BBD chorus and vibrato that sounds both luxurious and genuinely strange, sometimes in the same preset. It covers the classic lush shimmer you’d expect from any well-built chorus, but the Warp knob pushes it somewhere closer to a warped tape deck, which is where it really earns its name.
Controls
The two large knobs handle the basics: Speed sets the LFO rate, and Depth controls how wide the pitch swings. A center toggle flips between chorus and vibrato mode. Then three smaller knobs let you go deeper. Amp is a clean boost for the overall output, useful for pushing your amp into breakup and getting a little grit behind the shimmer. Freq shifts the tonal emphasis of the modulated signal, letting you dial more warmth or brightness into the effect. And then there’s Warp. According to the manual, it introduces a delay in LFO regeneration that causes intense warped-vinyl and detuned rubber-band sounds. Even a small nudge noticeably loosens up the modulation. Cranked, it’s unstable and disorienting in a way that Depth alone can’t reach. In the demo above I’ve set up sweeps for Depth, Speed, and Warp so you can hear exactly what each one does in isolation.
How It Sounds
The Liquid Chorus preset gives you a good sense of the baseline: Speed at 6, Depth at 4, and Warp just below the midpoint for a hint of looseness without going off the rails. It’s rich and full without being syrupy. Lush Classic pulls back the Warp to 1.5 and bumps Depth to 5, which is closer to a straight lush chorus voice, the kind that flatters clean arpeggios and chord voicings. Tape Vibrato switches the toggle into vibrato mode, turns Warp up to 8, and rolls off the Freq to give the whole thing a warmer, woollier texture, more worn-out tape than pristine pitch modulation.
The most dramatic territory is Psychedelic Warp, where Speed is maxed at 10 and Warp is also at 10. It’s genuinely unhinged, with the modulation losing any predictable pattern and becoming a sloshing, swimming swirl. The Amp knob in the Detuned preset is cranked to 5, which shows how the boost stage integrates with the effect: you get dirty, saturated modulation rather than just a clean shimmer with more volume.
Koldwave vs Echo Fix EF-P3 Chorus Vibrato
The Echo Fix EF-P3 Chorus Vibrato is another analog BBD chorus-vibrato worth comparing. The EF-P3 has a Waveshape control to blend between sine and triangle LFO curves, and a Resonance knob that feeds the vibrato signal back into the BBD chip for a warbly, resonant quality. Both pedals can reach lo-fi and unstable territory, but they get there differently. The EF-P3’s tools are more about shaping the wave itself; the Koldwave’s Warp knob messes with LFO timing in a way that feels less controlled and more physical, like something slipping out of sync. The Koldwave also adds the Amp boost, which the EF-P3 doesn’t have. If you want precision over your wave’s shape, the EF-P3 is the call. If you want something that can sound genuinely broken in an interesting way, the Koldwave is the one.
Who It’s For
This is a great pedal for players who want more than one flavor of modulation from a single box. The chorus side is lush enough for clean, ambient playing. The vibrato side with Warp pushed is genuinely weird enough for experimental and psych-adjacent sounds. The Amp knob makes it work well into a slightly pushed amp, not just squeaky-clean rigs. One note from the builder: the input stage can clip with hot-output pickups depending on your Amp setting, so if you’re running active pickups or a hot humbucker, keep that in mind. If you’re after a pristine, controlled shimmer with nothing unusual going on, a simpler pedal might suit you better. But if you want a chorus that can do classic and strange, the Koldwave is worth a close look.
