Forte

Forte is a collection of instruments you play in the browser, 63 of them. What makes it special is that nothing is recorded: every sound is computed live in the browser from the physics of the instrument — how the strings are strung, how the hammers strike, how the air shakes in the pipes, all by the real principles. The author, Jesse Thaler, writes in the very first line of the README: Vibe coded by Jesse Thaler. It has no stars on GitHub yet, but the repo already has 1,050 commits and 37 releases, with the latest commit just hours ago.

The instruments fall into five groups: 19 traditional ones, including piano, harpsichord, pipe organ and carillon; 11 electric ones, including the Hammond organ, Rhodes piano and Ondes Martenot; 8 historical experiments, including da Vinci's bowed clavier and Franklin's glass harmonica; 16 physical phenomena, where you can play a black hole, a pulsar or singing sand dunes; and 9 pieces of research equipment, with particle accelerators and gravitational-wave detectors turned into keyboards.

Playing is straightforward: the bottom two rows of the computer keyboard are the keys, and touch screens and MIDI keyboards work too. Every instrument lets you turn the knobs real instruments hide — the shape of the string, where the hammer lands, where the pickup sits, even how fast the black hole spins. Each instrument page has a "How it works" section that lays out the equations used, the papers cited and the simplifications made — it is as much a physics lesson as a toy.

The limits are real too: all the sound is computed live in the browser, so a slow computer or phone will stutter; the tone is a physical model's sound, not a sample, so it does not have the feel of a "real instrument" recording; and a few instruments are still being polished in the workshop. You also have to turn the sound on to get anything out of it — a screenshot cannot tell you what it sounds like — and Chrome, Edge or Firefox on a computer work best.