So like render the snare to audio, render the kick, etc. and then mix them all. Would that then reduce CPU usage?
1 Answer
It depends where you're doing any other processing on the kit.
By the time it's rendered (bounced to audio), CPU isn't an issue & the rendering itself is non-realtime, so it doesn't matter.
If you're using the kit plugin's own mixer, groups, compressors, EQ etc, then bouncing each individual instrument or mic will affect how the compressors, group busses & channel gains interact.
For instance - I use Toontrack's Superior Drummer.
I can bounce every single mic to its own track & then deal with it as though I had actually recorded all those mics dry & live.
This is a big job - 20 or 30 mics coming into the board, no EQ, no grouping, no sub-mix... it's "pure" but it's a lot of work. I've done it sometimes, but not often. If I do it this way the first thing I'm doing is patching up a lot of noise-gates to tame the bleed (spill), then dropping the right mics to the right busses. (Yes, It's a plugin, I can simply switch the bleed off entirely, but if you're gonna do it properly... do it properly ;)
However... I'm far more likely to simply render the plugin's stereo output - using the already sub-mixed channels inside the plugin, maybe some slight onboard EQ or comp... & then treat that as a stereo pair for the rest of the session. It retains a certain "live" quality to it, every mic interplays with the others, the individual close mics, the spill into the other mics on the kit & the array of overall ambient mics available. It gives a solidity I would take me an hour to get back with the individual mics rendered, even if I do really prefer my own comp/EQ to those in the plugin.
If I change my mind, I can just trash the bounce, tweak & bounce it again.
Simple.