Most of my favorite groove-tweaking is done manually, but there are a number of automated techniques that are worth knowing as well.
It’s easy to overlook the fact that as of Live 8, audio can be quantized just like MIDI.
The quantize commands are under the Edit menu. If they are grayed out, click on the waveform display of the sample you want to quantize, then try again.
If you’re new to quantizing, here are good settings to get you started:
After clicking OK, you’ll see something sorta like this:
A warp marker has been created for every single transient, and each has been moved to the closest 1/16th note grid line. If you’re trying to sync up a loop to a rigidly steady beat, this can be a great way to start. It’s also a cool place to begin if your goal is to seriously mangle and reprogram a beat – all the warp markers get created leaving you to ready to drag individual transients around all you want.