Ozone Imager: How to Use iZotope's Free Stereo Imager, What Stereoize Does, and a Settings Chart by Job

The short answer: Ozone Imager is iZotope's free stereo imaging plugin (AU, AAX, VST2 and VST3, 64-bit only), built from the Imager module in Ozone and included with every version of Ozone. It does three things: a Width control that turns the side channel down (to nothing at -100%) or up (by up to 6 dB at +100%), a Stereoize switch with two modes that creates width from mono sources, and three vectorscope views plus a correlation meter that show you what the width is doing. The free plugin works on the whole signal at once; for a different width in each frequency band, iZotope points you to the Imager module in full Ozone. Use it on individual sounds and buses, start with Stereoize II on mono sources, keep the master to a few percent at most, and keep the correlation meter in its positive half. A widener makes a part feel bigger. It can't make a mix wide that was arranged narrow.

I master my own releases (Sony, Universal, Ultra, Dim Mak, 50M+ streams) and other people's songs as a service, and Ozone Imager is the free pick in the best stereo imaging plugins. I also sell an Ozone mastering chain that uses the full Imager module, disclosed at the end.

What's in the free version

Download it from iZotope's site and nowhere else. It's free, though iZotope may ask you to sign in with a free account to get it.

The window is freely resizable, which helps when you're reading the vectorscope. iZotope lists recent macOS and Windows versions and the major DAWs as supported; requirements change, so check its page before you install.

What the free version doesn't do is split the signal into bands. Width and Stereoize act on the whole sound, lows included. In full Ozone, the Imager module handles up to four bands (iZotope's Ozone 9 and Ozone 11 documentation both say so), so you can keep the lows mono and widen only the top. More on that further down.

Stereoize I vs II

Width alone does nothing to a mono source: there's no side channel to turn up. iZotope's Ozone documentation says the same of the Imager module, where Width only affects mono input once Stereoize is on. Stereoize builds the side channel first, then Width decides how loud it is.

iZotope says neither mode compromises the mono compatibility of the source, because both only add side content, and side content drops out when you sum to mono. The other half of that, also from iZotope's own tips: anything you widen tends to lose some level in mono. A stereoized synth falls back to its dry mono self on a phone speaker. Nothing cancels, but there's less of it, so set its level with that in mind.

Reading the meters

• Polar Sample draws a dot for every sample. In iZotope's Ozone documentation, patterns inside the 45-degree safe lines are in phase, and patterns outside them are out of phase.
• Polar Level draws rays instead: the length shows level, the angle shows where in the stereo field that energy sits.
• Lissajous is the classic oscilloscope view. A vertical line means the two channels are the same (mono); a horizontal one means they're working against each other.
• Correlation sits beside the scope. iZotope's advice is to keep it in the positive half of its range. A reading that keeps dipping below 0 on the loudest section is a part that will thin out or vanish in mono.

The free plugin's views match the ones in iZotope's Ozone documentation; labels can change between versions, so the plugin window is the authority. If you want correlation per frequency band, or a correlation readout next to a spectrum, Voxengo SPAN carries one too.

Ozone Imager settings chart, by job

These are starting points, not iZotope's defaults. The 50 to 60% for mono sources is iZotope's own tip: turn Stereoize on, slide Width up to 50 or 60%, then adjust the Stereoize slider until the image balances. On a master, the same tips article tries 25% and calls it a bit exaggerated; with a single-band imager, a few percent is plenty. If the top of a bass needs width while its sub stays mono, that's a multiband job.

How to set it up

1. Install it from iZotope's site in the format your DAW uses (AU, AAX, VST2 or VST3).
2. Insert it on a track or bus, not the master. Width works best on the sounds that should be wide: pads, synths, backing vocals, effect returns. The kick, bass, snare and lead vocal stay centered; what stereo imaging is covers where everything goes.
3. Read before you touch anything. Loop the loudest section and watch the vectorscope and the correlation meter. Some sounds are already wide enough.
4. Set Width, or Stereoize then Width. Stereo sources only need Width. Mono sources need Stereoize on first; start with Mode II.
5. Compare at matched loudness. More side content reads as louder and better for a few seconds. Bypass at the same level before you keep a setting.
6. Check mono. Sum the mix to mono in your DAW, or drop a second Ozone Imager last on the master at -100% and bypass it afterward. If a part vanishes or the hook thins out, pull the width back.
7. Automate it if the song wants contrast. iZotope's tips suggest narrowing a bridge and opening back up for the final chorus. A chorus feels wider when the section before it was narrower.

When the free version isn't enough

The free plugin is single-band, so it's the wrong tool for widening a full mix or anything with real low end. The Imager module in full Ozone splits the signal into up to four bands, and Ozone 10 added Recover Sides, which iZotope describes as folding the side content you remove when narrowing back into the center instead of losing it. In iZotope's documentation, Stereoize still applies to all bands equally inside the module; Width is what you set per band. The Ozone mastering chain guide shows where the Imager sits in a full chain.

Other free tools cover the jobs Ozone Imager doesn't: Polyverse Wider for widening mono sounds (Polyverse says it stays mono compatible), and Voxengo Correlometer for correlation per frequency band. They're compared with the paid options in the best stereo imaging plugins. For vocals, a doubler on a send usually beats an imager on the lead; the best vocal doubler plugins covers those.

Mistakes that make width sound cheap

• Widening the master instead of the parts. Two different parts panned left and right are wider than one mix stretched by a plugin.
• Widening the low end. Bass and sub belong in the center below roughly 100 to 120 Hz. A single-band imager widens them along with everything else.
• Stereoize on everything. It's for mono sources. On a sound that's already stereo, it adds smear, not size.
• Width on width. A widened synth, a stereo chorus and a wide reverb on the same part is how it disappears in mono.
• Mixing on headphones only. Headphones exaggerate width. Check speakers, a phone and mono before a width decision stays.

Where I land (and the disclosure)

Ozone Imager is the free imager I'd install first: Width, two Stereoize modes, and meters that teach you what width looks like, on individual sounds and buses, checked in mono. On my masters, width is two small moves: the lows go mono, and the top gets a touch more side than the mix had, never more than survives a mono check. That's a multiband job.

The full Imager module is the imaging stage in the Ultimate Master Chain for Ozone: seven Ozone modules (EQ, Vintage Compressor, Low End Focus, EQ, Exciter, Imager, Maximizer), gain-staged, with version-matched builds for Ozone 9, 10, 11 and 12. It needs Ozone Standard or Advanced; the free Imager can't load it. I'm biased; the free Imager is worth installing whatever you master with.

Quick answers

Is Ozone Imager free? Yes. iZotope offers Ozone Imager as a free download (AU, AAX, VST2 and VST3, 64-bit only), and it's also included with every version of Ozone. You may need a free iZotope account to download it.

Is the free Ozone Imager multiband? No. The free plugin works on the whole signal at once. The Imager module inside full Ozone splits the signal into up to four bands, so you can keep the lows mono and widen only the top.

What's the difference between Stereoize I and II? Mode I uses a Haas-style delay to turn mid content into side content, which iZotope calls a colorful phasing effect. Mode II uses decorrelation and convolution and sounds subtler. Start with Mode II on most mono sources.

Does Ozone Imager hurt mono compatibility? Stereoize only adds side content, so iZotope says it doesn't compromise the source's mono compatibility, but widened parts get quieter in mono. Keep the correlation meter in its positive half and check the mix in mono after every width move.