The AceTone Electronics CSW-01 California Swirls is an all-analog chorus pedal, a type of effect that doubles your signal and detunes the copy for a shimmering, swirling sound. Pedal of the Day describes it as capturing "the warm, swirling textures that defined classic rock, new wave, and grunge" tones, and places it among the chorus pedals that use bucket brigade technology, the delay-line chip design behind classic analog chorus circuits.1
The three knobs
The CSW-01 keeps its control layout simple: three knobs. Despite that, Pedal of the Day's reviewer found it has a lot of range, writing that "With just three knobs, this refreshing beauty has a lot of range, moving easily from light chorus to slightly warbled to big, vintage vibrato tones."1
| Control | What it does |
|---|---|
| Cutback | Adjusts the speed of modulation, from slow, sweeping waves to faster, more animated swirls1 |
| Surf | Determines the intensity of the effect1 |
How it sounds
AceTone's circuit is voiced for a warm, slightly compressed character, which the reviewer attributes directly to the bucket brigade chip: "The bucket brigade technology ensures the warm, slightly compressed character that digital circuits simply can't replicate." The same review describes the pedal's output as "smooth, liquid swells with a slightly dark, organic quality."1
That range, from subtle thickening to full vibrato, puts the California Swirls in territory that players might otherwise reach for with a dedicated vibrato pedal, though the CSW-01 approaches it from the chorus side1.
Videos
Pedal of the Day
Tom’s Pedal Demos
Questions
Is the AceTone CSW-01 California Swirls analog or digital?
It is an all-analog chorus pedal. Pedal of the Day describes it as built around a genuine bucket brigade chip, the delay technology used in classic analog chorus circuits, and credits it with a warm, slightly compressed character that the reviewer says digital circuits cannot replicate.
What does the Cutback knob do on the CSW-01?
Cutback adjusts the speed of the modulation. At one end it produces slow, sweeping waves, and at the other faster, more animated swirls. Together with the Surf knob, which sets the intensity of the effect, it covers the pedal's range from light chorus to vibrato.
Can the California Swirls do vibrato sounds?
Yes. Pedal of the Day found the three-knob layout moves easily from light chorus to slightly warbled tones to big, vintage vibrato sounds, so the pedal covers more ground than its simple control layout suggests.
Sources (1)
- AceTone Electronics CSW-01 California Swirls Analog Chorus, Pedal of the Day, 2026-05-26