The Untempered Cosmos

R. Andrew Lee

About this app

The Untempered Cosmos is not a song. It is closer to a wind chime, or a fountain, or a room with a good view. You put it on and let it run, and over time you start to hear what it is doing.

Preview it now at theuntemperedcosmos.com. The app turns the piece into a room you can stand inside: each star anchored to a position around you, the chord holding still as the sky turns.

When you open it, the app reads your location, looks up which stars and planets are above your horizon at that moment, and assigns each one a sustained sine tone. The brighter the object, the louder. The higher in the sky, the more present. Each tone is placed in the stereo field to match where its object sits in the sky. As the Earth turns, stars rise and set, and the chord changes with them.

There is no playback in the usual sense. Nothing is recorded, nothing repeats. Two people listening at the same instant from different cities will hear something different. The same listener returning at midnight will hear something different from what they heard at dusk.

The piece is tuned to a single low D, with every audible tone a whole-number ratio above it. This is just intonation, the tuning choirs drift toward when no piano is forcing them to compromise. Sine tones have no harmonics of their own, so the only thing creating consonance between two of them is how cleanly their frequencies divide into each other.

Eighty-eight objects: the Sun, the Moon, the five naked-eye planets, and eighty-one named stars down to magnitude 2.5. Each constellation is treated as a chord and tuned with intent. Some carry shimmer pairs, two stars detuned by fractions of a hertz so they beat slowly against each other.

Best on headphones. The spatial design places each tone in three dimensions around you, rendered with Valve's Steam Audio. Lock-screen play and pause controls keep the piece running while the phone is locked. Audio focus is honored — calls, navigation prompts, and other apps pause and resume the piece cleanly.

By R. Andrew Lee. A work in progress; the catalog will keep growing.

What’s new

The Moon has been rebalanced. Its higher voice now carries the low end, with the octave beneath it much quieter, so the bass sits under the piece instead of on top of it. The difference is clear on speakers or anything with a subwoofer, and subtle on earbuds. Stopping no longer clicks, including from the lock screen. Star names now appear only once a body is genuinely audible, so the list fills in gradually through twilight instead of arriving all at once.