Metronomes of course, have been around forever. As early as the 70's a lot of bands started syncing to an electronic source. Especially the prog bands, with excellent drummers, who were versatile enough to sync at will to the arpeggiators on analog synths. And even those arpeggiators often had tempo drift due to the analog electronics.
I looked in the archive for this article -- an amazing collection of data by the way -- and found U2 tracks with tempo variations all over the map:
This project has created some amazing data, but I don't agree with all the conclusions at face value. Some of the stuff that is labeled as too machine-like, is well within the discipline of a lot of drummers. Meanwhile modern click tracks can be easily programmed to speed up and slow down throughout a track. In fact, it's done all the time.
EDIT: One other thing, some of the most interesting intentional tempo variations occur in the cycle of measures, phrases, and sections. The data presented here, only measured in seconds, doesn't track that relationship which would be the most musically interesting thing. It would be a good experiment to listen to some of these tracks with a prompt following the timeline in real time.
Metronomes of course, have been around forever. As early as the 70's a lot of bands started syncing to an electronic source. Especially the prog bands, with excellent drummers, who were versatile enough to sync at will to the arpeggiators on analog synths. And even those arpeggiators often had tempo drift due to the analog electronics.
I looked in the archive for this article -- an amazing collection of data by the way -- and found U2 tracks with tempo variations all over the map:
http://labs.echonest.com/click/?trackId=TRKYQTC123E85932E2&#...
http://labs.echonest.com/click/?trackId=TRZFYJM123E85816BE&#...
And then others, just a year or two earlier in their career, more "machine"-like:
http://labs.echonest.com/click/?trackId=TRYMXDV123E8593F96&#...
http://labs.echonest.com/click/?trackId=TRJTTTN123E8593796&#...
This project has created some amazing data, but I don't agree with all the conclusions at face value. Some of the stuff that is labeled as too machine-like, is well within the discipline of a lot of drummers. Meanwhile modern click tracks can be easily programmed to speed up and slow down throughout a track. In fact, it's done all the time.
EDIT: One other thing, some of the most interesting intentional tempo variations occur in the cycle of measures, phrases, and sections. The data presented here, only measured in seconds, doesn't track that relationship which would be the most musically interesting thing. It would be a good experiment to listen to some of these tracks with a prompt following the timeline in real time.