Step Audio is an Oregon-based maker of MIDI guitar effect controllers and pedalboard tools, founded by Bill Wardlow. Originally established as Molten Voltage in 2006, the company rebranded to Step Audio in 2016 to focus exclusively on patented products. Wardlow — an intellectual property attorney, programmer, and lifelong guitarist — designs each product for the demands of touring professionals, branding the line as "Road-ready MIDI Machinery."

The company's flagship product, the Pilot Wave, is a MIDI effect sequencer capable of controlling up to ten pedals simultaneously, dynamically modifying their parameters in sequences of up to 16 steps. The Riff-Step transforms the DigiTech Whammy into a pitch-shifting sequencer, unlocking harmonies and note patterns beyond the Whammy's standard capabilities. The lineup also includes the STATUS MIDI display and clock mapper, the TEMPODE MIDI clock generator and injector pedal, the MIDI Splitty 1-in-6-out MIDI splitter, and the One Trick Pony, a compact coin-cell-powered MIDI controller.

Under the earlier Molten Voltage name, the company's Molten MIDI 2 pitch-shifting sequencer was adopted by Ed O'Brien of Radiohead and Vernon Reid of Living Colour. Other artists associated with the brand include members of Metallica, Trey Anastasio, Bob Weir, and Steve Vai.

Step Audio has 8 products cataloged on Equipboard, including MIDI Foot Controllers, MIDI Interfaces, and Effects Pedal Accessories. Their gear is featured by 1 artist, with the strongest followings in Rock. Notable users include Jack White.