Gravity Machine

What it does

A generative instrument built on physics. Up to four orbs are flung around a walled room, and every wall or orb collision plays a note from the chosen scale, with the point of impact setting pitch and the physics setting timing. Gravity, a central mass, orb size, a surface feel from heavy to ice and eight room shapes decide how long the movement lasts. Sixteen scales, eleven tuning systems, a chord chain, a 16-voice pluck engine with reverb and per-orb MIDI channels sit around that.

In the demo

Jade opens it standalone and pushes each physics control to its extremes, then quantises individual orbs to a half, quarter or sixteenth to thin the notes out. She builds a three chord sequence, fires an explosion every two bars, then runs it in AUM with the four orbs sent to a piano, two pads and String Lab.

Worth knowing

Jade spends a while on how small the controls are on an iPad and finds no way to scale them up. A Mac and Windows build is $50 from the developer’s site.