If using VSTis like Kontakt or HALion Sonic (pictured), which can multiple instruments simultaneously, then unless you’re just layering sounds, it’s a good idea to route each to a separate DAW track, and render each as a separate audio file.
When exporting tracks for mixing, do I export my group sections, like Ac Guitars, from the stereo bus, or should I export from the Ac Guitars group track? Also, when sending my bass, snare or kicks to their respective group tracks, should those group tracks be stereo or mono? Things I read say that the group tracks for these instruments should be in stereo. But that doesn’t make sense to my brain, when I’m also told that I have to export these as mono files! So... are they exported as mono from a stereo group track? If it makes a difference, these would mostly be MIDI/VST instruments that I’m talking about.
SOS Forum post
SOS Reviews Editor Matt Houghton replies: Let’s park the issue of the type of instruments you’re using for now; I’ll get back to that later. There are some general conventions you can follow to give a mix engineer what they need. That means audio files in the desired format (eg. 24‑bit 48kHz WAVs), all starting at bar one, beat one to make them easy to line up, and with mono files for mono signals and stereo files for stereo ones, and each and every file clearly labelled so it’s easy for anyone to discern what the job of each file is intended to be.
If mixing someone else’s recordings, I’d want access to the full multitrack recordings, including individual tracks for every virtual instrument, as well as bounces of any important aux send effects, again all clearly labelled. Even if the effects end up not being used or being replaced, this gives the engineer an understanding of your intent. I might or might not subgroup ‘stems’ to be bounced — I tend to create my own groups for my mix anyway, and probably want to process/automate the individual tracks feeding them.
It’s good practice also to provide a brief note (eg. in a text file or email) detailing things like the project tempo and other useful information. You might also provide the tempo in a MIDI file, particularly if the tempo changes, and you might include in that MIDI file all the virtual instrument parts too — preferably with each part on a separate MIDI channel, so it’s easy to ‘explode’ it onto different tracks. That can be a helpful backup, in case the engineer feels the need to replace sounds or layer in new ones.
The only golden rule is to start by checking with your mix engineer what their personal preferences are, so you can deliver what they want.
But like I said, these are conventions and tips, not ‘rules’. The only golden rule is to start by checking with your mix engineer what their personal preferences are, so you can deliver what they want/need.
If you and they use the same DAW, it could just be a question of tidying up the session and sending it to them, making sure to ‘consolidate’ your edits, and include all the media files. That said, it’s unlikely they’ll have access to all the same plug‑ins as you, so you’ll still probably need to render/bounce any instruments and processing as audio — as that’s useful for project archival, it shouldn’t be too much of a chore!
Regarding your specific question about group tracks being mono or stereo, I suspect you’re overthinking this one. It’s not the end of the world if mono stuff is bounced in stereo, but it does take up more storage space and processing power when mixing, and it’s just one more job for the engineer to burn time (your money) on; there’s a reason there’s software dedicated to stripping out the extra channels!
For me, the answer to that question really depends on the purpose of the groups. If I want to route several instruments to a group to give me control over all of them on a single track — the way I’d use subgroups on an analogue mixer — then I’d almost always create stereo groups. Why? Well, some sources will be stereo in any case, but even with mono sources I might want to pan them differently, or use something a like stereo ambience reverb before compressing. But I’d generally create such groups specifically for mixing — and your mix engineer will likely be happy to do the same. So it really only becomes an issue if you’re planning on bouncing and sending those groups.
However, if using groups just to combining multiple tracks to create the composite mono sound of one instrument (for example, blending two mics used to capture an acoustic guitar or guitar cab), you might well choose to use a mono group, and export that rather than the individual tracks.
Finally, let’s return to the matter of virtual instruments. I’ve discussed the MIDI, and the mono/stereo aspects above. But also consider that if using single plug‑ins to play multiple sounds (eg. a virtual drum kit, or a multi‑instrument player like Kontakt or HALion), then consider feeding each instrument to different DAW tracks, to give the mix engineer separate control over each element. Also, assuming you’re bouncing to 16‑ or 24‑bit audio, check that the level on each individual track doesn’t exceed 0dBFS True Peak. If, for instance, you’re using gain at the group or master busses to bring the level down, the individual tracks could still be peaking high, so will clip when you bounce them — and note that lots of VSTi presets have an unhelpfully hot output by default (to make them catch your ear when auditioning!).
So, there’s lots to think about. But the bottom line is this: if exporting for someone else, ask what they prefer, make sure the files are sensibly named, and take the opportunity to create audio‑only multitracks anyway, for a future‑proof archive of your project!