The Camelot wheel: a five-minute guide to harmonic mixing

Two songs can have identical tempos and still sound terrible together. The reason is key. Harmonic mixing is the practice of blending songs whose keys are compatible, and the Camelot wheel is the tool that makes it easy.

What the wheel is

The Camelot system, created by Mark Davis of Mixed In Key, labels the 24 musical keys with a number from 1 to 12 and a letter. A is a minor key, B is a major key. A song in A minor is 8A; its relative major, C major, is 8B.

The numbers are arranged like a clock because they follow the circle of fifths: each step clockwise is up a fifth.

The rule

From the key you are on, these moves sound good:

1. Same key. 8A to 8A. Always safe.
2. One step clockwise or anticlockwise. 8A to 9A or 7A. A fifth apart, closely related.
3. Switch the letter. 8A to 8B. The relative major or minor, with the same notes.

That is the whole system. Count to one, or swap the letter.

Energy boosts

Two moves are used for effect rather than smoothness:

• +2 steps (8A to 10A) lifts the energy noticeably.
• +7 steps (8A to 3A) is a semitone up, a classic lift for a final chorus.

Doing it in practice

1. Find each song's Camelot key. Our free BPM and key detector reads it from a file in your browser.
2. Pick your next song from the neighbours on the wheel.
3. Match tempo. A gap of a few percent is fine; bigger gaps need a tempo change, which shifts pitch unless key lock is on.
4. Mix over a phrase, usually 8 or 16 bars, so the overlap is long enough to be heard as a blend.

Try the interactive Camelot wheel to see the compatible keys light up.

When to break the rule

Harmonic mixing is a guide, not a law. A short echo-out or a hard cut hides key clashes because the songs barely overlap. Percussive intros and outros mix with anything. And a lot of popular music is ambiguous about its key anyway, which is why Everplay stores a confidence score and only gates the moves that expose both songs when it is sure.