by RoJeC on 25 Dec 2020, 10:52
key lock has nothing to do with BPM detection. This feature applies to playback key when pitch is changed.
The BPM detection is an algorithm that tries to set a beatgrid for the whole track. However some tracks are not following a fixed (EDM) rhythem (beat/cycle/bar). Especially live music, music with 'silence breaks' or with varying BPM are off.
For these tracks you have to set manually.
If the algorythm would provide more flexible beatgrid this would lead to many other consequences in e.g. syncing and tempo usage.
It's a bit general answer to your question. In the end the skills of the DJ are needed to blend the creative work of artists/producers into a great set. And an algorythm can make it easier to get familiar with tracks key elements. But it can't beat the ear of a DJ.