How To Get A Wide Stereo Image When Mastering

There are genres where having the widest possible mix certainly is a goal to aim for from the early stages of the production. The song arrangement, the instrumentation, space it was recorded in, microphone and preamp choices all have an impact on the stereo image, and each contributes to the end-result.

That being said you can definitely over-cook stereo width in your songs. Over-doing it can turn a great sounding record into a total mess.

In this article, we’ll take a look at a few ways to enhance the stereo image of your track during the mastering phase of the production process.

How to get a wide stereo image when mastering

Essential Pre-Widening Knowledge

It’s important to know that, as with achieving a 3D sound or getting your song to be really loud, the majority of the stereo image is created during the production and mixing. That’s not to say that there’s quite a bit we can do during mastering!

Our brains need a frame of reference of what ‘wide’ sounds like. To create an incredible sense of width, some elements or sections of your song will need to be positioned predominantly in the center. This is something to consider when crafting both the arrangement and the mix.

Also note that if you widen the image too much, you might  diminish the song’s groove. ​​​​​​​If you spread the groove elements (drums, guitars, piano, keys, arps) too far apart, they’ll stop sounding and feeling connected to each other.

First and foremost, check what your stereo image looks like. REFERENCE’s Stereo Width module is great for this. Getting a feel for the stereo width of your original track, as well as the reference, will help you pinpoint what changes, if any, you need to make to it. You can use panning in your DAW, or a stereo tool to change the width of any frequency range in your track. 

How to know how much stereo widening to apply during mastering


Traditional stereo EQing can deal well with stuffy areas of a mix, but it’s not typically used as a widening tool.

Some plugins let you monoize low frequencies using elliptical filters. Centering (from a panning point of view) the low frequencies brings focus to the most powerful tracks, whilst allowing the others have more room around the mix. 

Use Izotope imager to monoise your signal

Some producers simply remove the low-end from the ‘side’ channels using a mid side EQ.

Cut the sides using a mid-side EQ to focus the low-end

We’re going to take a look at a few M/S techniques…What is M/S (mid-side), you say?

In short, a stereo audio signal can be split into left and right channels, or it can be split into mono and stereo information.

The M(id) signal contains all the elements that are the same in the left and right channels, such as sounds panned to the center. The mid also contains the sounds that exist only in the right channel or only in the left channel.

The S(ide) signal contains the difference between the left and right channels. Stereo reverbs, stereo modulation effects, and instruments that were recorded in stereo that are hard panned contain information that lives in the sides of your track.

Mid-Side infographic

Using MIXROOM is one of the best, most transparent ways to increase the width of your stereo image.

Open the plugin, set 2 of the bands to ‘side’. Use one of them to reduce the level of the low frequency content in the sides. Some people go as high as 80Hz, but it all depends on the particular song you’re mastering.

The second band should be set somewhere in your high-top end; again, this depends on the song. Use this band to boost the frequencies by a couple of dB and you’ll hear the whole thing open up.

Using MIXROOM to get great stereo width during mastering

Remember that clearing out muddiness in the track will also open up the sides of your mix.


Be careful and gentle with using it. You can very easily ruin the mix using M/S processing, so make sure your ears can hear fine-enough details to know when you’re going into the red zone. (Headphones can be helpful here).

There are a couple of ways to go about this: you can GENTLY expand the side signal, focusing on the quieter elements of the sound. Bringing them up in volume will make the side signal be more consistent. Using a dynamic mid-side EQ for this is a great way to pinpoint speicifc frequencies and keep the dynamic processing subtle. 

Mid-side compression for stereo width

Alternatively, gently(!!!) compress the mid signal to restrict the dynamic range, effectively pushing the lead instruments (vocal, snare, kick, bass) down into the mix. This can potentially bring up the side signal and widen your mix.

Mid compression for stereo width

Bonus M/S technique:

Use a mid-side encoder-decoder like Voxengo’s MSED (it’s free!). Lower the Mid level by 0.5dB at most. This is enough to make a pretty obvious impact on the stereo image.

Another tool which lets you change the level of the mid or side of your mix is Waves’ Center. This plugin enables you to shift the balance, frequency content, and the punch of the track from the mid to the sides. 

This last feature is incredibly useful when you want to center the punch of your EDM song so it sounds more consistent in clubs. Because the music played there is usually in mono, this can be a very important step in the production process.


A multi-band imager such as iZotope Ozone’s Imager module is the go-to tool for widening. There are single-band tools like Softube’s Weiss MM-1 which also work great if you need less granular control over how the stereo image is effected.

Generally, with Ozone’s Imager, you want to set 3-4 bands, and then click “Learn” to have the plugin place the crossover points at the ‘safest’ spots in the frequency spectrum.

Following this, you can adjust the width of each band as necessary. Starting with Ozone 8, iZotope introduced a second mode for the module’s Stereoize function. “Stereoize” lets you enhance width in a mono-compatible way, meaning you won’t hear weird comb filtering when listening to the song on your phone, for example.

iZotope Ozone’s Imager module is the go-to tool for widening

In most genres, you can imagine the stereo image looks like a rose: you want it to be narrow at the bottom and widest at the top of the frequency spectrum. Bass narrowest, low-mids and mids wider, high-mids wider still, with the top end being the widest.

LEVELS by Mastering The Mix can help you keep an eye on your stereo width and will warn you if you over-do it. Pushing the width too wide can give you phase issues that can make your mix sound thin. the Stereo Field section in LEVELS will turn red if phase issue creep into your mixes. 

At The End Of The Process, 

…use EXPOSE to analyze your track and your references. This makes it easy to see 2 very important things. 

Audio quality control application

The first is you get to see how your track fares overall in terms of dynamic range, stereo image, and peak levels. If there are any issues based on the preset you’ve selected (Spotify, Youtube, Club etc), the relevant section will turn red. 

Second, you can compare the tonal balance of your track with your references, which lets you assess how your master compares to commercially successful tracks. Is your track too wide? Too loud? Is the hip-hop song you’re mastering lacking in 100Hz punch? 

With the Compare EQ section of EXPOSE 2, you can view how the tonal balance of your ‘side’ channels compares with your reference track. This will tell you how wide your track is compared to your reference track. If the EQ line in EXPOSE is showing -3dB in the high-end, this means you need to boost the width of your production by 3dB in the side channels to match the width of your reference track.

 EQ compare in EXPOSE 2

At the end of the day, the ONLY thing that matters is serving the song. Neither the artist, nor the listener care what tools you used to get the track sounding amazing. You care. Pick your tools carefully so they work for you, not against you.

By Mastering The Mix Contributor - Tiki Horea

Tiki Horea

Starting off as a drummer and continuing as an engineer, I've been involved in the music industry all of my professional career. I fell in love with mixing and mastering other artists’ music. Every musician deserves to get goosebumps when they listen back to the finished mixes. This is what gets me up in the morning.