The DLS RotoSIM features a charmingly uncluttered user interface, sporting easy-to-understand controls.
A bypass switch turns the effect on, while a second footswitch toggles between slow and fast speeds that are set with a knob each.
A ramp knob sets how quickly the speed changes. Separate knobs adjust the top and bass rotor levels, and an authentically- voiced overdrive - with the level controlled by a single knob - can be brought in with a mini-toggle switch.
There's also plenty more variation to be had if you fancy a tinker around inside the chassis, with no less than seven more adjustments available.
All in all, cool sound and smooth operation from a great US boutique pedal.