Elastic Beatgrids

Elastic Beatgrids

This page groups info relevant to tracks with multiple BPMs.

MIXXX support

• Mapping commands: mixxxcontrols?#master
• Manual (Preferences): https://www.mixxx.org/manual/latest/en/chapters/preferences.html?highlight=analyse#beat-detection
• Forum post: https://www.mixxx.org/forums/viewtopic.php?f=3&t=11629
• GSOC project 2020: measures_downbeats_bars_and_phrases
• GSOC project 2018: gsoc2018ideas?#beatgrid_enhancements
• Zulip Chat: https://mixxx.zulipchat.com/#narrow/stream/109171-development/topic/Rhythm.20Detector
• Serato Comparison: here

Definitions

Tracks with multiple BPMs

There are two types of tracks that have multiple BPMs:

• a) Unsteady BPMs:
• Definition: these tracks floats around a single BPM (+-1% range). Examples:
• Live drummers: Guns N' Roses - Sweet Child O' Mine
• Old disco / 80s Pop tracks: Matia Bazar - Ti Sento
• b) Transition Tracks:
• Definition: these tracks have clear BPM changes (+-10% range). Examples:
• Abrupt 85->115 bpm: Magic Drum Orchestra - Drop it like its Hot

• Smooth 126->98 bpm: Planet Soul - Set me Free

See also this wiki page: iconic_tracks

more lists: list1 list2

Elastic Beatgrid use cases

"Elastic beatgrids" is a feature that explicitly allows multiple BPMs in each track.

Without elastic beatgrids, the following becomes impossible to perform without the audience noticing:

• Beatjumps:
• Impossible to fix in advance because the jump happens instantaneously
• FX BPM-synced effects: (eg delay)
• Impossible to fix in any situation, because FX fully depend on the beatgrid
• AutoLoops:
• IN point: with quantize off, you have to enable the loop at precisely the right time
• OUT point: In this case you have to immediately enter "loop out adjust mode" to fix the out point as fast as you can
• Sync beatmatch:
• In this case you HAVE to compensate continuously using the jogwheels on the whole transition (manual beatmatch)