Possibly our most asked question for Auto-Align is how to go about drums alignment, which microphone should be the reference etc.
First, Auto-Align looks for correlation in the signal to calculate the optimal time and phase correction for the mics. This is important to remember when choosing the SEND and RECV sources for each track. e.g. using the the top tom mic as a reference for the kick mic will probably won't yield very good results...
Since the snare drum has a rich frequency content and is placed virtually at the center of the drum kit, the top snare mic is a great place to start as the initial reference for the overheads and room mics. Try aligning both left and right overhead and room mics to the top snare for the clearest snare sound and most accurate transients reproduction. Don't be shy with the Noise Floor settings, as we'd rather miss some beats than feeding Auto-Align with irrelevant bleed.
Next, we'll align the bottom snare mic to the top snare mic and continue to align the toms and hi-hats to the overheads.
When aligning the toms, hihat and kick mics to the overheads, it's important to feed Auto-Align with the sound of those drums for the detection process rather than that of the snare, or you will simply be aligning the bleed of the snare into those mics. For best results, align the toms and hi-hat mics to their nearest overheads.