Dont Rely and think that You HAVE to use songs that are in key…remember it is just a tool.
Mixing in Key is only important when you are mixing Synths, and Vocals. As well 1-5bpm difference will not really affect the key of the song.
Basslines also have a key signature but it is not as dominate and most people will not really notice if u are mixing 2 basslines that are out of key.
Harmonic mixing is really important if you are doing extended mixes…ie blending 2 tracks together for more than say 16-32 beats.
But also remember that its only really important if both tracks have synth lines or vocals layered with a Synth line in it.
so example…if track A is lets say 9A on the camelot wheel…and i think track B which is 5A would do really well next…ill just do a basic blend when there is 1 min left (thats usually where the outtro begins) and bring in track B…since track A has a basic drum/percussion usually the blend with track B will sound completely fine as there is no harmonics to clash with.
There are also times when 2 songs that totally shouldnt go together based on MIK or keyfinder…that actually go REALLY well.
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