Mix with music key
A music key is something well known by musicians: it is the main tone of a music track. It is used by DJs which follows the harmonic mixing techniques.
Basically if you want that the next track you will play is harmonically compatible with the current one, then you have to select a track with a compatible key. The Circle of fifths shows how to determine which key is compatible with the current one (using tone notation). Compatible keys are:
- close to the current one from one clockwise or counter-clockwise step.
- close to the current one from one upper or lower step.
Most of the time DJs are not using tones as music keys but an equivalent clock representation using hours. This notation was defined and used by Mixed in Key. It is called the Camelot wheel: http://www.harmonic-mixing.com/Images/camelotHarmonicMixing.jpg.
Using this wheel, most compatible keys are one hour less (-1) or more (+1) or minor (A) or major (B). Example with 7A:
- 6A and 8A are compatibles
- 7B is also compatible.
First of all you have to analyse your audio collection to calculate music keys for all tracks. For that, configure the base path of your music collection and then click on the Scan keys button 
. It could take from one to several seconds per track, so be patient. You should see the music key of a track in the file browser.
Then load a track on a deck. To know which other tracks are compatible, click on the Key button 
of this deck. Compatible tracks are highlighted:
- in green: if the key is one tone more (+1) or less (-1)
- in orange: if the key is from major (B) to minor (A) or the opposite
That's it! If you mix only compatible tracks together then your set will be lovely and smooth :-)