Bellows

The Bellows is a compact transistor-based dirt pedal that sits between amp-style overdrive and fuzzy saturation. It is not modelled on a specific circuit. Its character changes a lot with the Drive setting: low settings give a dynamic, amp-like breakup, and fully clockwise settings give heavy saturation. The design keeps the full frequency response of the instrument, so the maker also points to bass use.

There are two controls. Level sets the output volume by adjusting the transistor's bias voltage, and a small amount of noise while setting it is described as normal. Drive sets the input gain; counterclockwise it is thinner and cleaner, and clockwise it is thicker with more growl.

The pedal is true bypass, using electronic relay-based switching, so no audio passes when it is unpowered. It runs from a 9V battery or a standard 9V DC supply with a 2.1 mm negative-centre barrel connector. The maker recommends pedal-specific, transformer-isolated supplies and warns against higher voltages.