[signalflow]

using "identify beat" can also help in this situation, edit menu (apple i). trim the audio file from the first transient or down beat. use shuffle so the file snaps to 1|1|00. put it in slip mode. this is bar 1, beat 1. next, count the beats and find bar 2, beat 1 and identify that beat-2|1|00, make sure to zoom in to get right on the attack. in slip mode this allows you to freely place the cursor (unlike grid mode). then bar 3, beat 1 etc. soon, you'll see a bunch of different tempos in the tempo field-example, 87.56, 88.77, 86.95, 88.45 etc. the more beats you identify, the more you'll see an average tempo. if you think you're in the ball park, say 88 bpm's, change the tempo at 1|1|00 to 88, put it in grid and hit play. if your file has been trimmed correctly and you got the right tempo, your file should be locked in to the groove. make sure to erase all of the other tempo markers in the tempo field. click on them and hold then drag down to edit window. you'll see a small trash can appear, then let go of the mouse. if it's off a little, try 87 bpm's, 89 or 87.50 etc. once the beat is locked to the right tempo, editing should be seemless. dealing with hip hop drums, you should have no problem finding the tempo quickly. it might sound time consuming but it's not. just a few quick key strokes and you're there.
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