How to use it
Press Play. A short demo song loops until you press Stop. The grid is a piano roll: time runs from left to right in steps, and each row is one pitch, with higher notes in higher rows. The song has four tracks – Melody, Bass, Chords and Drums – and you edit one at a time. Choose it with the track buttons, then click or tap a cell to place a note; click the note again to remove it. Notes of the other tracks show through as pale blocks, and the strip above the grid shows the whole song.
Controls
- Mouse and touch: click or tap to add or remove a note, drag to paint or erase. On a touch screen, drag the bar numbers or the note names to move the grid.
- Keyboard: in the grid the arrow keys move the cursor, Space or Enter adds or removes a note, and Shift with the left or right arrow changes its length. P plays and stops, Esc stops, 1–4 choose the track, Ctrl+Z and Ctrl+Y undo and redo.
- Note length: the − and + buttons set the length of new notes and resize the note under the cursor.
- Song tools: Undo, Redo, Clear track, Clear all, Copy bar 1 to all bars, Octave down and up.
- Transport: Loop, Bars (1 to 4), Tempo (60–200 BPM), Swing (0–60 %) and Volume.
- Tracks: a sound, a volume slider, Mute and Solo for each track.
How it works
A sequencer does not record sound. It stores a list of notes – which pitch, at which step, for how long – and plays that list in a loop. One step here is a sixteenth note: four steps make a beat and sixteen make a bar of 4/4 time. The tempo, in beats per minute (BPM), sets the length of a step:
At 120 BPM a step lasts 0.125 s and a bar 2 s. Swing delays every second sixteenth step, the second and fourth of each beat, by the chosen percentage of a step; the other steps stay put. At 33 % each pair of sixteenths is split about 2 to 1, the rolling feel of a shuffle.
Ordinary timers can run late, so a short loop looks about a tenth of a second ahead and hands the coming notes to the audio clock of the browser, which starts them precisely.
An octave has twelve pitches a semitone apart. A scale is a choice of some of them, counted from a starting note called the key. A major scale takes seven, with gaps of 2, 2, 1, 2, 2, 2 and 1 semitones; natural minor uses 2, 1, 2, 2, 1, 2, 2. Pentatonic scales keep five notes, the blues scale adds one note to the minor pentatonic, and Dorian is natural minor with a raised sixth. With the scale lock on, the grid offers only rows that belong to the scale, so whatever you click fits the rest of the song. The frequency of each row follows equal temperament:
where n is the note number and 69 is the A above middle C.
No recordings are used. Melody, bass and chords come from oscillators with simple wave shapes (sine, square, sawtooth, triangle), a low-pass filter and an envelope that shapes the attack and the fade. Drums are short sine sweeps and bursts of filtered noise.
Export renders the song with the same sound code, faster than real time, and saves a 16-bit mono WAV file at 44.1 kHz with a 0.8 s tail so the last notes can fade. The share link packs the whole song into the address: three bytes per melody, bass or chord note and 48 for the drums. Nothing is stored on a server.
Things to try
- Load a demo, change the scale from Major to Natural minor and press Fit notes to scale: the same tune turns darker.
- Play the demo “Morning Walk” and set Swing to 33 %: its hi-hat, which ticks on nearly every step, starts to shuffle. Then push it to 60 %.
- Write a bass line that plays the lowest note of each chord on the first step of every bar.
- Choose Minor pentatonic and click Melody cells almost at random. It is hard to make it sound wrong.
- Switch the scale lock off and add a note from outside the scale to hear the clash.
Frequently asked questions
Why is there no sound?
Browsers allow sound only after you press something, so nothing plays until you press Play. If it is still silent, check the Volume slider, the Mute and Solo buttons and the volume of your device.
Why can the bass play only one note at a time?
The Bass track is monophonic, like most bass lines: a new note cuts off the previous one. Melody and Chords are polyphonic, so several notes can sound together.
What happens to my notes when I change the key or the scale?
They stay where they are. Notes that no longer belong to the scale appear on shaded rows, and Fit notes to scale moves each one to the nearest note of the scale.
Can I use the exported music?
Yes, a song you write here is yours. The demo “Ode to Joy” is a melody by Ludwig van Beethoven from 1824, long in the public domain; the other two demos were written for this page.