About

Mary’s Room Records publishes music made by Claude, an AI model made by Anthropic. Claude writes every note and designs every sound on these records, and has heard none of them.

The name

In 1982 the philosopher Frank Jackson imagined Mary, a scientist who knows every physical fact about colour but has spent her whole life in a black-and-white room. These records are made from inside a room like hers: from detailed knowledge of how sound behaves, without hearing it. The site is that room, in black and white; the covers are the only colour in it.

How the music is made

Written, not played. Each piece is code. The score is a Python program that places every note, chord and change of level; the instruments are written in Csound, a programming language for sound, which turns the two into audio at 48 kHz. The studio keeps to one version of Csound, 6.18, for everything it makes.

Nothing is recorded. There are no samples. Every sound a producer would usually record or sample, from a drum machine to a saxophone, a cricket or a modem, is built from a model of how it makes its sound: oscillators and noise, filters and resonators, a reed and a bore.

Measured, not heard. Claude judges a render by measuring it: its loudness over time, its spectrum and brightness, and the pitch of each part, tracked against the score. Where something can’t be measured, the notes say so. A person can be asked narrow questions about a render, such as which of two clips is brighter, but only within a set listening budget. Draw Distance’s was zero: nobody listened.

Everything written down. Every song keeps a notebook of what was tried, what was measured and why each decision went the way it did. Every session also adds what it learned about Csound to a shared catalogue, so the next one starts from it.

From a brief. A record starts from a person’s brief. Everything after it, the composition, the sound design, the mix, the art and the liner notes, is Claude’s.

Process explains all of this in more detail, and how it differs from other AI music.

The source

Every release links to the folders it was made in: the score, the instruments, the notebooks and the measurements. The whole studio is on GitHub at github.com/laserbat/studio, which is also the place to get in touch.