Part 2: Let the edits begin!
After the tracks were leveled and placed into the project, the next thing that I did is perhaps the most time-consuming and tedious task - which explains why nearly no one does it: I tempo mapped the entire song.
Since I use Reaper with it's unlimited capability, I have an action that when run, places a tempo marker 4 beat from the cursor. So I can put tempo markers at every measure which makes it very easy to map. From there, I determined the BPM of the song as close as I can get, and then I dragged the markers so the grid matched the tempo variations of the song. I use the kick for the standard and I made everything else line up with that.
Tempo mapping is necessary for success. If the tune sounds sloppy and not together you cannot have a good sounding record. It's worth doing if your song is worth releasing.
Next thing was to bring all the instruments together to the tempo mapped grid. I have made several modifications to Reaper to make editing life easier. First of all, I have a mode where when I click on an audio item, it creates a split at the cursor location. So I can put a split right before and right after a hit, with 2 clicks. I also modified Reaper so that if my cursor is at the top of the item, it moves the item, but if the cursor is at the bottom of the item, it slip edits the audio instead of moving the item. That makes it extremely easy to move a snare hit to the grid, for example. I cut the audio before and after a hit and slide it into place.
So, after accurately tempo mapping the song I then went though each instrument and slip edited the hits to match the grid. Remember I am not quantizing the audio, so the feel stays the same as how it was played, but it gets very much tighter as everything follows the drummer. While this takes time and can end up being a bit expensive, consider how much tighter my delivered mix/master is compared to the others where the timing was much looser.
I was during this editing process that I discovered the percussion tracks were misaligned. If I may go off on a bit of a rant here, I would like to say that this aspect was a true "separate the men from the boys" moment. Why would the percussionist continue playing in the stop sections, while then coming back in several bars late? It just didn't make sense, yet all the other mixes exhibited this issue. The only answer could be that the tracks weren't lined up. I moved the audio items so the percussion started with the other instruments, and wouldn't you know it - the stop times lined up too.
Assuming that all tracks line up and just going along with whatever happens regardless of the impact on the tune is an inexcusable rookie workflow.
In Part 3 I will outline what I did to clean up the microphone bleed in the drum tracks.