How To Multitrack: Advice for Musicians and Producers
I first got into multitracking back when Eric Whitacre did a Virtual Choir with his composition Lux Aurumque. Little did I know this skill set would come in handy a decade later among musicians stuck at home in self-isolation. Some videos I’ve done include:
Pentatonix: Run To You - Cello Choir Multitrack and
Franz Biebl: Ave Maria - Cello Choir Multitrack
But it was the most recent one I put together for a friend & colleague that got the most attention:
Can this be done live?
Not really. Latency issues. The only way to reliably do this at the moment is for every musician to record their part separately. The recordings are then compiled into video editing software (i.e. multitrack). Easiest way is with an app called Acapella. It’s not very powerful and it has many limitations, but if you’re not a technical geek, and you don’t have access to a technical geek, try the app. Otherwise, you’ll have to do it the hard way.
The two challenges are matching pitch and tempo among musicians that can’t hear one another. Both can be addressed by creating an in-ear reference track to which the musicians can play. The less desirable option is to just give the musicians a metronome marking (or a video of a conductor) and pray the tuning will be close enough.
How do I create a Multitrack?
Instructions for Musicians
Your Producer should have given you either a reference track or a metronome marking. Do not proceed without one of these, otherwise your project will likely fail.
Have your digital metronome or reference track on a device other than the one you will use to record yourself. Plug in some headphones and cover only one ear so you can hear yourself through your other free ear.
Set up your recording device around 2 meters away from your instrument. The distance isn’t crucial; what’s more important is that everyone has a similar distance.
Make sure you can see yourself in your recording. Double-check your framing if using a real camera, or just keep an eye on the screen if you’re using your phone’s selfie cam.
Start the video recording. Make sure you can see a time counter showing how long you’ve been recording. Take your time and don’t rush; this part will be edited out. Get yourself ready to play.
Put in your earbud and start your reference track or metronome. Don’t be afraid to re-start if you didn’t nail the beginning. Again, this part easily gets edited out.
Once you start the recording, do not stop, don’t redo any measures, just keep playing. If you’re not happy with something, redo the entire take.
[Optional: If it’s a really long recording and you want another crack at one or two particular passages, record those separately and ask your producer if they can replace the audio for that section (helpful to give them a time stamp). They may need to be bribed.]
Leave some silence at the end so your Producer has some room to work with.
[Optional: At the end, your Producer may have asked you to clap on a certain beat. Be as precise with this as possible; it will be used to line up all the tracks later.]
End the recording and play it back so you ensure it’s all there.
Send the recording to your Producer via a lossless platform. If it’s small enough, send via email. Otherwise, use a file-sharing service such as Dropbox. Do not use YouTube, WhatsApp, Facebook Messenger, iMessage, SMS, etc. as they compress the video and deteriorate the sound quality.
Instructions for Producers
This section assumes you have some video/audio editing knowledge. If you don’t, but want to learn, the program I used to put everything together was Sony Vegas Pro, only because I’m familiar with it. But it’s neither free nor widely used, so I wouldn’t recommend it. Adobe Premiere Pro is industry standard but $$. Davinci Resolve is free and extremely powerful.
[Edit: As of June 2020 I am now using DaVinci Resolve exclusively. It is resource-hungry and I had to double my RAM and set up an eGPU for my laptop, but it was worth it.]
If this all sounds like too much, get in touch with me (or someone else who knows their way around a video editor) for a quote.
Create a reference track. Either download a rendition of the piece to which the musicians can play along, or create a midi file.
Open the reference track in a DAW (or even your video editor) and create a separate click/spoken track for the purposes of counting musicians in and maintaining tempo during long notes, particularly the ending cutoff. Consider creating another track on which you record spoken instructions (e.g. “rit coming up”).
[Optional: At the end of the track, immediately after the last note has finished, record the following instructions: “Don’t stop the recording just yet, but free up both hands now and get ready to clap. I’ll count to 5, and when I do, clap loudly ON BEAT FIVE. Ready… Here we go… 1, 2, 3, 4, 5!”]
Render the file (don’t forget to adjust levels so the extra tracks don’t distort) and send via email or file-sharing such as Dropbox to your musicians.
When you get the files back, toss them all into a new project. If everyone has recorded their parts correctly, all you should need to do is line up the parts in order to hear some awesome music. Lining up the parts will be even easier if all your musicians did the clap at the end, just zoom in on that and line up the spikes on the audio track.
Give each video track its own size, position, and crop. Or layer them. Or pan/fade/switch between them. The world’s your oyster. Different programs do this differently, so Google/YouTube is your friend if you don’t know how.
Normalize all audio tracks and set levels for preferred balance & voicing. Due to auto compression in phones, you might have to chop up the audio parts and set different sections of each track at different levels.
Pan different audio tracks with different combinations of L/R balances. This will give the overall recording a sense of space.
Add a bit of reverb. A BIT.
If you need to manipulate someone’s tempo or entry, you can split the track at the point of the error and again a few seconds on either side, then gently expand/compress that track’s timeline to match other parts. Keep video grouped with audio so it doesn’t look funny. There’s no limit, besides your sanity, to how many times you can do this. It is theoretically possible to have an entire orchestra sending in individual recordings at completely different tempi & interpretations, and still get everyone to play perfectly together. But you will lose much hair and many CPU cooling fans.
If you need to adjust intonation, try Melodyne. Careful: this can be catastrophic with multitracks, as sometimes all parts can be out-of-tune together, and making just one part absolutely in tune (equal tempered) can wreak havoc on everything else. Proceed with caution.
Trim the tracks to the start/end points of the music. Do any fancy fade-ins/outs you want to do, both for video and audio.
Render at 1080p or YouTube quality mp4.
Hope this helps. Sorry it’s not easier.