Tag Archives: audio mastering

Review: iZotope’s Ozone 9 isn’t just for mastering

By Pat Birk

Izotope is back with its latest release, Ozone 9. And with it, iZotope hopes to provide a comprehensive package of tools to streamline the audio engineer’s workflow. The company has been on my radar for a number of years now, having used the RX suite extensively for clean up and restoration of production audio.

I have always been impressed by RX’s ability to improve poor location sound but was unfamiliar with the company’s more music-focused products. But, in addition to being an engineer, I am also a musician, so I was excited to try out the Ozone suite for myself.

Ozone is first and foremost a mastering suite. It features a series of EQ, compression, saturation and limiting modules meant to be used in a mastering chain — putting the final touches on your audio before it hits streaming platforms or physical media.

Since Ozone is primarily (though by no means solely) aimed at mastering engineers, the plugin features a host of options for manipulating a finished stereo mix, with all elements in place and no stems to adjust. Full disclosure; My mastering experience prior to this review comprised loading up an instance of Waves Abbey Road TG Mastering Chain, applying a preset and playing with the settings from there. However, that didn’t stop me from loading a recent mix into Ozone and taking a crack at mastering it.

The Master Assistant feature helps create a starting point on your master. Note the colored lines beneath the waveform, which accurately depict the song’s structure.

Ozone has deeply integrated machine learning and I immediately found that the program lives up to the hype surrounding that technology. I loaded my song into the standalone app and analyzed it with the Master Assistant feature. I was asked to choose between the Vintage and Modern setting, select either a manual EQ setting or load a mastered song for reference and then tell Ozone whether the track was being mastered for streaming or CD.

Within about 15 seconds of making these selections and playing the track, Ozone had chained together a selection of EQs, compressors and limiters that added punch, clarity and, of course, loudness. I was really impressed with the ballpark iZotope’s AI had gotten my track into. Another really nice touch was the fact that Ozone had analyzed the track and assigned a series of colored lines beneath the waveform to represent each section of the song. It was dead on, and really streamlined the process of checking each section for making adjustments.

Vintage
As a musician who came up listening to the great recordings of the ‘60s and ‘70s, I often find myself wanting to add some analog credibility to my largely in-the-box productions. iZotope delivers in a big way here, incorporating four vintage modules to add as much tube and transistor warmth as you desire. The Vintage EQ module is based on the classic Pultec, emulating its distinctive curves and representing them graphically. My ears knew that a little goes a long way with Pultec-type EQs, but the graphic EQ really helped me understand what was going on more deeply.

The Vintage Compressor emulates analog feedback compressors such as the Urei 1176 and Teletronix LA2A and is specifically designed to minimize pumping effects that can appear when compression is overdone. I had to push the compressor pretty hard before I heard anything like that and found that it did a really nice job of subtly attenuating transients.

Vintage tape adds analog warmth, and this reviewer found it pulls the sound together.

The Vintage Limiter is based on the prized Fairchild 670 limiter and it does what a limiter is meant to do: raise the level of the mix and decrease dynamic range, all while adding a distinctive analog warmth to the signal. I’ve never gotten my hands on a Fairchild, but I know that this emulation sounds good, regardless of how true it is to the original.

The Master Assistant feature arranged all of these modules in a nicely gain-staged chain for me, and after some light tweaking, I was well within the neighborhood of what I was hoping for in a master. But I wanted to add a little more warmth, a little more “glue.” That’s where the Vintage Tape module came in. iZotope has based its tape emulation on the Studer A810. The company says that the plugin features all of the benefits of tape — added warmth, saturation and glue — without any of the wow, flutter and crosstalk that occurs on actual tape machines.

Adjustable tape speeds have a noticeable effect on frequency response, with 7.5ips being darker and 30ips being brighter. More tonal adjustments can be made via the bias and low and high emphasis controls, and saturation is controlled via the input drive control. The plugin departs
from the realm of physical tape emulation with the added Harmonics control, which adds even harmonics to the signal, providing further warmth.

I appreciated the warmth and presence Vintage Tape added to the signal, but I did find myself missing some of the “imperfection” options included on other tape emulation plug-ins, such as the Waves J37 tape machine. Slight wow and flutter can add character to a recording and can be especially interesting if the tape emulator has a send-and-return section for setting up delays. But Ozone is a mastering suite, so I can see why these kinds of features weren’t included.

The vintage EQ purports to offer Pultec-style cuts and boosts.

Modern Sounds
Each of the vintage modules has a modern counterpart in the form of the Dynamics, Dynamic EQ, EQ and Exciter plugins. Each of these plugins is simple to operate, with a sleek, modern UI. Each plugin is also multiband with the EQs featuring up to eight bands, the Dynamic EQ featuring six and the Exciter and Dynamics modules featuring four bands each. This opens up a wide range of possibilities for precisely manipulating audio.

I was particularly intrigued by the Exciter’s ability to divide the frequency spectrum into four quadrants and apply a different type of analog harmonic excitement to each. Tube, transistor and tape saturation are all available, and the Exciter truly represents a modern method of using of classic analog sound signatures.

The Modern modules will also be of interest to sound designers and other audio post pros. Dynamic EQ allows you to set a threshold and ratio at which a selected band will begin to affect audio. While this is, of course, useful for managing problems such as sibilance and other harsh frequencies in a musical context, problematic frequencies are just as prevalent in dialogue recording, if not more so. Used judiciously, Dynamic EQ has the potential to save a lot of time in a dialogue edit. Dynamic EQ or the multiband compression section of Ozone’s Dynamics module have the potential to rescue production audio.

Exciter allows for precise amounts of harmonic distortion to be added across four bands.

For instance, in the case of a fantastic performance during which the actor creates a loud transient noise by hitting a prop, the Dynamic EQ can easily tame the transient noise without greatly affecting the actor’s voice and without creating artifacts. And while the EQ modules in Ozone feature a wide selection of filter categories and precisely adjustable Qs, which will no doubt be useful throughout the design process, it is important to note that they are limited to 6dB boosts and 12dB cuts in gain. The plugin is still primarily aimed at the subtleties of mastering.

Dialogue Editors, Listen Up
Ozone’s machine learning does provide two more fantastic features for dialogue editors: Match EQ and Master Rebalance. Match EQ intelligently builds an EQ profile of a given audio selection and can apply it another piece of audio. This can aid greatly in matching a lavalier mic to a boom track or incorporating ADR into a take. I also tested it by referencing George Harrison’s “What Is Life?” and applying it to a mix of my song. I was shocked by how close the plugin got my mix sounding like George’s.

Ozone’s standard equalizer

Master Rebalance, meanwhile, is meant for a mastering engineer to be able to bring up or lower the vocals, bass, or drums in a song with only a stereo mix to work from. I tested it on music and was very impressed by how effectively it raised and cut each category without affecting the parts around it. But this will also have utility for dialogue editors — the module is so effective at recognizing the human voice that it can bring up dialogue within production tracks, further separating it from whatever noise is happening around it.

Match EQ yields impressive results and could be time-saving for music engineers crossing over into the audio post world — like those who do not own RX 7 Advanced, which features a similar module.

The Imager module also has potential for post. Its Stereoize feature can add an impressive amount of width to any track and has a multiband feature, meaning you have the option to, for example, keep the low frequencies tight and centered while spreading the mids and highs more widely across the stereo field. And while it is not a substitution for true stereo recording, the Stereoize feature can add depth to mono ambience and world tone recordings, making them usable in the right context.

Master rebalance features a simple interface with

The collection of plugins is available at three price points — Elements, Standard and Advanced — which allows engineers to get started with Ozone at any budget. Elements is a stripped down package of Ozone’s bare essentials, Standard introduces the standalone app and a sizeable step up in terms of featureset and Advanced is replete with every mastering innovation IZotope has developed to date, including new toys like Low-End Focus and Master Rebalance. A complete list of each tier’s corresponding features can be found on Izotope’s website.

Summing Up
Ozone 9 integrates an immense amount of technology and research into a sleek, user-friendly package. For music recording and mastering engineers, this suite is a no-brainer. For other types of audio post engineers, the plugin provides enough perks to be interesting and useful, from editing to design to final mix. Ozone 9 Elements, Standard and Advanced editions are available now from IZotope.


Pat Birk is a musician and sound engineer at Silver Sound, a boutique sound house based in New York City.

Cinelab London adds sound mastering supervisor and colorist

Cinelab London, which provides a wide range of film and digital restoration services, has added two new creatives to its staff — sound mastering supervisor Jason Stevens and senior colorist Mike David.

Stevens brings with him over 20 years of experience in sound and film archive restoration. Prior to his new role, he was part of the archive and restoration team at Pinewood Studios. Having worked there his whole career, Stevens’ worked on many big films, including the recent Yesterday, Rocketman and Judy. His clients have included the BFI, Arrow Films, Studio Canal and Fabulous Films.

During his career, Stevens has also been involved in short films, commercials and broadcast documentaries, recently completing a three-year project for Adam Matthew, the award-winning digital publisher of unique primary source collections from archives around the world.

“We have seen Jason’s enviable skills and talents put to their best use over the six years we have worked together,” says Adrian Bull, co-founder and CEO of Cinelab London. “Now we’re thrilled to have him join our growing in-house team. Talents like Jason’s are rare. He brings a wealth of creative and technical knowledge, so we feel lucky to be able to welcome him to our film family.”

Colorist Mike Davis also joins from Pinewood Studios (following its recent closure) where he spent five years grading feature films and episodic TV productions and specializing in archive and restoration. He has graded over 100 restoration titles for clients such as BFI, Studio Canal and Arrow Films on projects such as A Fish Called Wanda, Rita, Sue & Bob Too and Waterworld.

Davis has worked with the world’s leading DPs, handling dailies and grading major feature films including Mission Impossible, Star Wars: Rogue One and Annihilation. He enjoys working on a variety of content including short films, commercials, broadcast documentaries and Independent DI projects. He recently worked on Adewale Akinnuoye-Agbaje’s Farming, which won Best British Film at the Edinburgh Film Festival in June.

Davis started his career at Ascent Media, assisting on film rushes, learning how to grade and operate equipment. By 2010, he segued into production, spending time on set and on location working on stereoscopic 3D projects and operating 3D rigs. Returning to grading film and TV at Company 3, Davis then strengthened his talents working in long format film at Pinewood Studios.

Main Image: (L-R) Stevens and Davis

Quick Chat: AI-based audio mastering

Antoine Rotondo is an audio engineer by trade who has been in the business for the past 17 years. Throughout his career he’s worked in audio across music, film and broadcast, focusing on sound reproduction. After completing college studies in sound design, undergraduate studies in music and music technology, as well as graduate studies in sound recording at McGill University in Montreal, Rotondo went on to work in recording, mixing, producing and mastering.

He is currently an audio engineer at Landr.com, which has released Landr Audio Mastering for Video, which provides professional video editors with AI-based audio mastering capabilities in Adobe Premiere Pro CC.

As an audio engineer how do you feel about AI tools to shortcut the mastering process?
Well first, there’s a myth about how AI and machines can’t possibly make valid decisions in the creative process in a consistent way. There’s actually a huge intersection between artistic intentions and technical solutions where we find many patterns, where people tend to agree and go about things very similarly, often unknowingly. We’ve been building technology around that.

Truth be told there are many tasks in audio mastering that are repetitive and that people don’t necessarily like spending a lot of time on, tasks such as leveling dialogue, music and background elements across multiple segments, or dealing with noise. Everyone’s job gets easier when those tasks become automated.

I see innovation in AI-driven audio mastering as a way to make creators more productive and efficient — not to replace them. It’s now more accessible than ever for amateur and aspiring producers and musicians to learn about mastering and have the resources to professionally polish their work. I think the same will apply to videographers.

What’s the key to making video content sound great?
Great sound quality is effortless and sounds as natural as possible. It’s about creating an experience that keeps the viewer engaged and entertained. It’s also about great communication — delivering a message to your audience and even conveying your artistic vision — all this to impact your audience in the way you intended.

More specifically, audio shouldn’t unintentionally sound muffled, distorted, noisy or erratic. Dialogue and music should shine through. Viewers should never need to change the volume or rewind the content to play something back during the program.

When are the times you’d want to hire an audio mastering engineer and when are the times that projects could solely use an AI-engine for audio mastering?
Mastering engineers are especially important for extremely intricate artistic projects that require direct communication with a producer or artist, including long-form narrative, feature films, television series and also TV commercials. Any project with conceptual sound design will almost always require an engineer to perfect the final master.

Users can truly benefit from AI-driven mastering in short form, non-fiction projects that require clean dialog, reduced background noise and overall leveling. Quick turnaround projects can also use AI mastering to elevate the audio to a more professional level even, when deadlines are tight. AI mastering can now insert itself in the offline creation process, where multiple revisions of a project are sent back and forth, making great sound accessible throughout the entire production cycle.

The other thing to consider is that AI mastering is a great option for video editors who don’t have technical audio expertise themselves, and where lower budgets translate into them having to work on their own. These editors could purchase purpose-built mastering plugins, but they don’t necessarily have the time to learn how to really take advantage of these tools. And even if they did have the time, some would prefer to focus more on all the other aspects of the work that they have to juggle.