A classic Univibe® has a big sloshy sound but it’s kinda big and to manually control the rate you need yet another big pedal. The Neptune™ stays true to that classic ‘vibe tone without sucking out your midrange and it’s less than half the size. You can also manipulate one of the two sets of ‘Slosh’ (rate) controls by hovering your foot above its magic optical sensor.

Picture of the Tortuga Neptune Opto-Vibe