mixxxdj / mixxx

Mixxx is Free DJ software that gives you everything you need to perform live mixes.
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calculate and set the BPM from a loop length and time signature #9708

Open mixxxbot opened 2 years ago

mixxxbot commented 2 years ago

Reported by: beurotta Date: 2019-08-07T21:13:32Z Status: Confirmed Importance: Wishlist Launchpad Issue: lp1839388


The idea is to replace track's tempo with the one of a loop that has been set manually (with Loop-In, Loop-Out). It would be useful for tracks with a non-constant tempo.

A use case could be to play an original track that have been sampled by another artist, loop the sampled part, change the track's tempo with the one of this loop, sync the track that uses this loop and mix it. As "original" tracks are often played by a band, tempo is not constant and therefore hardly accurate on the looped part.

For now it has to be done approximately, by tapping the tempo of the loop and modifying BPM in file properties or by guessing the tempo while matching beatgrid and loop markers. Of course, it can not be done on the fly.

Instant loop takes the track's BPM and a bar length to calculate the loop length in seconds accordingly, but there is no way to do the opposite, although it is the same calculation.

(There are discussions on the forum about this feature but i couldn't find any similar request here.)

mixxxbot commented 2 years ago

Commented by: daschuer Date: 2019-08-12T06:30:30Z


I can think of another use case, a transition between two incompatible tracks, we may set a 3/4 beat loop and sync a 100 BPM track with a 120 BPM track. In this case the "from Track" needs to report the tempo taken from the uneven loop in order to make the sync feature work.