~*~ Sine Mix, by Sine Labs ~*~

Two songs become one, at your fingertips

Sine Mix is an instrument for the music you already love. Pick two songs and it hears their tempo, finds bar one and the key, and locks them together, so you can play the mix with your hands.

It runs in your browser and on iPhone, on one tape engine, and it is free to start.

Start free on the webGet it on iPhone

The specs

+----------+----------------------------------+
| Plays on | the web, and iPhone (TestFlight) |
| Stems    | vocals, drums, bass, melody      |
| Pads     | eight: four stems, four cues     |
| Presses  | land on the next beat            |
| Tempo    | measured from the drums          |
| Bar one  | from the kick and the clap       |
| Key      | one shift; the drums never       |
| Engine   | Rust, native and WebAssembly     |
| Library  | private to you                   |
+----------+----------------------------------+

The specs
Plays on	the web, and iPhone (TestFlight)
Stems	vocals, drums, bass, melody
Pads	eight: four stems, four cues
Presses	land on the next beat
Tempo	measured from the drums
Bar one	from the kick and the clap
Key	one shift; the drums never
Engine	Rust, native and WebAssembly
Library	private to you

How it works

Every song you add is split into four stems: vocals, drums, bass and melody. Then Sine measures it: the tempo from the drums, bar one from the kick and the clap, and the key.

Pick a second song and Sine moves it onto the first one’s grid, with one key shift if it needs one. The drums never shift, and bar meets bar.

Then the stems are yours to trade. The vocal from one song over everything from the other:

         vocals  drums   bass    melody
song a   [    ]  [ ## ]  [ ## ]  [ ## ]
song b   [ ## ]  [    ]  [    ]  [    ]

The pads

Mix is an instrument, not a playlist. Eight pads sit under your hands: the top four are the stems and the bottom four are cues.

Tap a stem to mute it, hold it to solo
Tap a cue to jump, hold it to mark the spot
Every press lands on the next beat, so nothing flams
A cue waits for the beat, so the groove holds

The tape

A mix should sound the same wherever you open it. Underneath Mix is one tape engine, written once in Rust:

The same engine on iPhone and in the browser
The two agree bit for bit
The tape brakes and starts on the beat, like a motor
Stereo on every route: headphones, speakers, the car
One screen of pixels that moves with the music

Agents

Every action in your library is also a command. The same verbs work by hand, in the sine command line and over MCP, so an agent can sort your songs and build a set.

$ sine mix library search night drive
$ sine mix collection create sunday
$ sine mix set build "late night drive" --bpm 118-128 --energy low

Today this door is Sine’s own. Opening it to everyone comes next.

Cost

Mix is free to start.

On the web: sign up at mix.sine-labs.com
On iPhone: the public TestFlight beta

Questions

Which songs can I use?

Your own. Upload the files you have, and they stay private to you.

Where does it run?

In the browser at mix.sine-labs.com, and on iPhone through the public TestFlight beta. Both play through the same engine.

Do I need headphones?

No. Mix plays in stereo on every route: headphones, speakers and the car.

Can I share what I make?

Yes. A shared mix opens as a link and plays in any browser.

Who made it?

Sine is made by Sine Labs. Mix is the first instrument. Studio, which takes any song apart and plays it new, comes next.

The idea is fusion and feel: songs you love should collide and genuinely fuse, and nothing should stand between what you mean and what you hear.