DIY Mix Prep, Pt. 2
In this series, we’re going over some of the most common issues I see with DIY mixes coming into my mastering studio. Today it’s all about phase! Hang onto your hats, it’s going to get a bit technical.
How to properly use a phase correlation meter
Please use a phase correlation meter when mixing! This tool should be placed on your master track, and you should be referencing it regularly as you mix.
Here’s what it should and shouldn’t look like:
Yes!
No!
How to fix phase issues in your DIY mix
If the meter looks like the pic that’s 👆, you could have phase issues present in your mix.
To fix this issue, you need to first find the offending instruments or mics causing the issue, and then adjust that individual track using one of these techniques:
-a micro-second level delay (such as a sample delay)
-an autophase plugin
-a micro spacing adjustment to a physical microphone
-manually dragging the waveform in your Digital Audio Workstation
Make sure you’re adjusting any tracks with phase issues to one single reference track. In rock music, this is usually the kick drum.
The “Opposite Method” of phase adjustment
Here’s some quick notes on phase adjustment using what I call the “Opposite method”.
To do this, we’re using our phase correlation meter on our master track, and a polarity flip on the out-of-phase track to intentionally get the audio as out-of-phase as possible. Then, when we return the polarity flip to its normal position, our audio will be as in-phase as possible.
Mono kick drum track panned maximum left
Out of phase mono mic track panned maximum right with polarity flipped on the track.
Hint: in Logic you can use the Utility-->Gain plugin to flip the polarity on any channel.
3. Now, look at your phase correlation meter, and listen and make very small micro adjustments until these two pieces of audio are as out-of-phase as you can get them. Closest to -1 on the meter as possible.
In headphones, you’re listening for only the kick drum in your left ear, and only the out-of-phase track in your R ear, with as little center bleed as possible between the two tracks.
4. To finish, take away the polarity flip on the right panned track, and return all your pan pots to center position. Now, you’ve got nice, clear, in-phase audio to work with.
5. Continue on, working through any additional out-of-phase audio as necessary, one track at a time, always using that same kick drum track as the phase reference.
Bonus tip: watch out for low end information that is hard panned; this can easily lead to phase issues. Reverbs are a common culprit here.
When you shouldn’t bother with phase adjustment
There is an important caveat to this process: doing all this phase adjustment is a quite technical and tweaky task, and it can easily knock you out of creative flow, preventing you from finding that next great idea while writing your music.
It’s a professional technique that should be used for a professional quality release. That doesn’t mean you should do it every single time when writing music at home.
If you’re working on a demo or something that’s rough and not for release, it’s probably best to prioritize the creative side and being speedy and fun in your writing, over going for highest professional quality and knocking yourself out of creative flow. There’s little point in wasting time making a song sound great, if the writing isn’t there.
We’ve got all the steps to a great mix laid out clearly for you on our Mixing Cheat Sheet! And, if you’re not a Patreon member yet, we’ve got even more great tips for you over there.
