Chromophone vs Chladni

Chromophone turns whatever is playing in the room into a living psychedelic picture. Play, sing, or put a record on: the visuals follow the sound as it happens. Every frame is built from the sound arriving right now. Low frequencies swing the whole shape, mids and highs cut the detail, sharp hits snap the pattern into a new one, and the mood of the music slowly steers color and scale. When the room falls quiet, the picture fades to black. Nothing is prepared in advance and no video file is playing behind the screen. The picture is generated on the device from what it hears at that moment, so what you see belongs to that moment in the room. WHERE PEOPLE USE IT Watching sound become picture. Put the phone down while music plays and let the room draw itself. On stage. Mirror the screen to a projector or a TV and let the visuals run through the whole set; the screen stays awake while it plays. In a stream. Keep a live backdrop moving behind a set instead of a looping clip that ignores the music. While you play. Point it at an amp, a piano or your own voice and watch what you are playing take shape. TWO THINGS TO KNOW BEFORE YOU START It makes no sound of its own. It listens, and the music comes from wherever you already play it: your playing, your voice, or a speaker across the room. It takes the system audio input, so a line from an external interface arrives exactly as a microphone does. In a silent room the screen goes dark, because nothing is ever faked. It draws for the moment, not for later. There is no export and no rendering: this is a live picture while the music is happening, not a clip to publish afterwards. NOTHING LEAVES THE DEVICE The app contains no networking code at all. Audio is analyzed on the device, frame by frame, and is never recorded, never stored and never sent anywhere. Switch on Airplane Mode and everything still works exactly the same. FOR PEOPLE WHO SEE SOUND If you have ever wanted music to look like the way synesthetes describe it, or watched sand jump into patterns on a Chladni plate, this is that idea driven live by the room around you.

In the 18th century the physicist Ernst Chladni drew a bow across a metal plate scattered with sand, and the sand arranged itself into a pattern. When a plate vibrates, certain lines stay perfectly still. The sand settles along those quiet lines, and the pattern appears. These are Chladni figures. This app recreates that phenomenon in the palm of your hand. Three thousand grains tremble on the screen and slowly gather along the nodal lines. It is made for watching that settling happen. What you can do - Four plates, twenty patterns: switch between square, circle, triangle and ring plates. Each has five patterns, twenty in all. Every plate has its own sand colours and its own range of tones. - Turn the dial: rotating the dial changes the pattern. The sand is not reset. It slowly rearranges itself from the shape it is in into the new one, and that rearrangement is the part worth watching. - Hear the tone: each pattern has its own pitch, and the range of tones moves with the plate you choose. Turn the sound off whenever you want to watch in silence. - Sing to the sand: turn on the microphone and hum a clear, steady note. The pitch of your voice selects a pattern within the current plate, and the volume sets how wildly the sand dances. Your voice is analysed on the device as it happens. Nothing is recorded and nothing is sent anywhere. - Fill the collection: save the patterns you like with a name of your own. The collection has twenty slots, and each saved pattern is given one to three stars according to how intricate it is. Mark favourites and filter to show only those. Tap a saved pattern to bring it back to the screen. - Export a wallpaper: save the current pattern as a 1179 x 2556 PNG in your Photos. It is not a snapshot of the screen. Grains of sand are redrawn along the nodal lines computed from the equations, so the sandy texture holds up at full resolution. The mathematics is computed, not drawn The circular plate uses Bessel functions and the triangle uses the exact Lame solution, and so on for each shape. Nothing is a prepared picture being played back. Every pattern comes from an equation solved on the spot. Free, and what the one-time purchase adds Watching, switching plates, sound, microphone mode, the collection and favourites are all free. Exporting a wallpaper is free too, but while the app is free the exported image carries a faint watermark of the app name, and a small banner ad sits at the bottom of the screen (it is hidden while the collection is open and while the opening screen is showing). A single one-time purchase removes that watermark and removes the ads as well. It is the only thing for sale and it is not a subscription. Without it you can still watch every pattern, fill the whole collection, and save wallpapers. Good to know - Ads: to keep the app free, a small banner ad supplied by Google is shown at the bottom of the screen. The one-time purchase removes it. - To show those ads, information about your device and about the ads you see may be collected by Google. If you decline the tracking request shown at launch, the advertising identifier is not used. Every feature of the app works either way. - No account required - The app connects only to load ads and to buy or restore the one-time purchase - Your collection is stored only on this device - Your voice is analysed on your device, never recorded and never transmitted - Available in 33 languages Take a moment and watch the pattern rise quietly out of the sand.