Extract Timing

Let's say you record a great audio track into Cakewalk Pro Audio. Wouldn't it be cool if you could apply the rhythm of that audio track to a MIDI track? The possibilities are endless. For example, you can have a MIDI percussion track double the (audio) guitar track, or simply Groove Quantize the MIDI tracks to the audio tracks.

For this example, we'll extract the basic rhythm of the guitar track in RIFFUNK.BUN. Next, we'll create a new MIDI track, based on the guitar rhythm. You can use any note for the MIDI track, but I'll use a cowbell (MIDI note G#4, or 56), since it's really percussive, and will compliment the guitar track.

1. Open RIFFUNK.BUN
2. Open the Audio view for the guitar track.
3. Click on the first audio event, then right-click to open the inspector menu, and choose Extract Timing.
4. Set the Trigger Level (%) to 3, and Minimum Length (ms) to 70. Do not select Find A Steady Rhythm.
5. Specify Convert Each Pulse To MIDI Note: G#4 and set Note Velocities to Vary With Pulse Level.
6. Click the Preview button, and you'll see red drum notes on top of the waveform. The drum notes represent the parts of the waveform that meet the criteria you specified in step 4.
7. Click OK, and the rhythm represented by the red drum notes will be pasted to the clipboard (as MIDI note events).
8. Choose Edit | Paste.
9. Set Repetitions to 8, and Starting at Track to 6. Click OK.
10. Set track number 6 to the MIDI port and channel that your drum sounds are configured for. General MIDI drums are on channel 10. If your keyboard/sound module is not General MIDI compatible, then the cowbell sound might not be assigned to note G#4. Simply find the correct note number, or use another sound. Play back the song.

Track number 6 will now play the rhythm of the guitar track. After step 6, you can select a MIDI clip, and use the clipboard as the source for Groove Quantize.

Unlike the example above, you should use the Find A Steady Rhythm option of Extract Timing if you want to extract the (steady) timing from a drum track. You have to experiment with the Trigger Level and Minimum Length values. Click the Preview button to verify visually that the values you entered "caught" the correct beats.

Experiment, and have fun!

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