How to Create a Linear Phase Deesser

Hey friend, thank you for watching another Sage Audio video.  Today I’m going to be showing you something a bit different – today you’re going to learn how to create a linear phase de-esser, which is something that currently doesn’t exist as a plugin, it’s not something you can buy.  It is however, something you can make yourself using some tools included in your daw, and certain plugins.

Now real quick, when a plugin is linear phase it means you can process the track, without affecting its phase.  This can be very useful when you have multiple tracks, and want to avoid phase cancellation amongst them – so I hope you’re excited to learn how to make this de-esser.  

But before we get started, if you’ve found this video or other Sage Audio videos to be insightful, please subscribe to our channel, and then click the link for notifications.  Also, if you’re an engineer or artist, or even both, and you have a mix you’d like to hear mastered, send it to us at SageAudio.com, and we’ll send you a free mastered sample of your work.

So what I have here are two tracks – one is in phase, one has an inverted phase.  Now before we go any farther, if you aren’t familiar with phase relations, or need a refresher, go watch our video on phase and null tests, titled “This One Test Can Change How You Mix Audio.” It’s full of great information on how phase relations work in audio.

So, again two tracks, one in phase, one inverted.  Now when set at the same volume, and processed identically, we should get complete phase cancellation, and no output as a result.  When we change one, some signal will be let through, and we’ll have only partial cancellation.

Let’s change one of the tracks then, using a linear phase EQ.  By using a low pass and a high pass filter, we create partial phase cancellation, in the frequency range that isn’t being cut off.  So frequencies here are being let through, and here are being let through, but between 2kHz and 8khz, we’re going to have phase cancellation, meaning that the frequencies in that range will be attenuated when these two tracks are played together, as if those frequencies had been eq’d out.  Let’s listen to a before and after so you can get a good idea as to how effective this is.

As you just heard, having the inverted phase track enabled changes the frequency spectrum significantly.  What’s more, if you adjust your channel fader, to change the level of this inverted phase track, you change the amount of sound being cancelled, which will affect how much of that high end gets cut out.  Take a listen.

So right now we’ve essentially created a roundabout way of making a linear phase EQ that can be adjusted with your channel fader, which is great, but what we can make from this point is even better.  If we use volume automation, to increase the volume of the inverted phase track, at points where esses are being sung, we have created a dynamic eq, that de-esses the vocal, without introducing unwanted phase cancellation, like a regular de-esser or dynamic eq would.  Granted de-essers are actually most often frequency specific compressors, but creating a linear phase, dynamic eq, will de-ess the vocal, in a way that other plugins can’t. So, if you’ve followed all these steps, congrats, you’ve made something that doesn’t exist in the audio world, and that’s pretty cool.

But let’s take one final listen to our tracks, using all these things put together, so we can hear the end result of this technique.  

And there you have it, a linear phase de-esser.  Now I can think of a couple other ways this technique could be accomplished, so if you want to do some experimenting or already have an idea as to how this would work, leave it in the comment section below.  That being said, I hope this video has been beneficial for you, if it has subscribe to the channel and click the link for notifications – that way you can stay up to date on our latest videos. And if you’re an artist or engineer, send your latest mix to SageAudio.com, and we’ll send you a free professionally mastered sample of your work.