Infinite Response is an Austin, Texas-based manufacturer of high-end MIDI keyboard controllers, best known for the VAX77 — a 76-key folding controller with a magnesium chassis, weighted action, polyphonic aftertouch, release velocity, and high-resolution (14-bit) velocity output. The VAX77 was first publicly demonstrated at NAMM 2009 and developed a reputation among players and reviewers as one of the most expressive master MIDI keyboards ever produced, with Keyboard Magazine describing it as a renaissance of the true high-end master MIDI keyboard.

The company later introduced the VAXMIDI, an open-source, semi-weighted hammer-action keyboard sold as an unassembled kit aimed at making the same expressive feature set — polyphonic aftertouch, release velocity, and hi-res velocity — available at a lower price point than the VAX77. Both instruments are designed primarily as controllers for software synthesizers and hosts such as Apple MainStage, Logic, and similar virtual-instrument environments, and the VAX77 includes a touchscreen for managing splits, layers, and patch changes onstage.

Infinite Response operates as a small specialist builder rather than a mass-market brand, and its instruments are most often discussed in MIDI controller communities focused on expressive performance, where polyphonic aftertouch and nuanced velocity response are the central concerns.

Infinite Response has 2 products cataloged on Equipboard, including MIDI Keyboard Controllers and Portable & Arranger Keyboards. Their gear is featured by 1 artist, with the strongest followings in Rock and Pop. Notable users include Eddie Jobson.