The Zoom B1 Four is a multi-effects processor designed for use with electric basses. Offered in an easy to use stompbox format, the B1 Four sports a wide selection of effects, amp emulations, and other features, such as an onboard 30-second looper and a chromatic tuner. With 68 built-in rhythm patterns, you can add drum loops to the mix, which can be quite helpful during looping. Distortion, chorus, and more are all on hand, as are 9 bass-amp models that simulate classic combinations. Five effects can be chained at any time and in any order. You can save these effects in one of the 50 user preset patches. Switch among patches (or banks of patches) quickly with the tap of a toe, so you can change your live or studio sound with ease. You can also change global characteristics to retain a sense of unity among patches. A three-knob tone stack and the overall output level knob do not change as you cycle through your sounds. The pedal sports 60 different effects, and you can edit or add more effects from your computer too. Simply hook the pedal up to your Mac or Windows machine over a USB cable and add effects from Zoom's Guitar Lab software. The B1 Four provides one 1/4" instrument input, one 3.5mm input for mobile devices and media players, and a combined amp/headphone output. The unit runs on four AA batteries, giving you up to 18 hours of run time. You can also power the unit with a dedicated ZOOM AD-16 AC adapter or over USB.