By Cory Choy

iZotope RX, a go-to audio repair and polishing suite for film, television, music videos and video games, has become so ubiquitous in the sound industry that “iZotope” has become a verb — “Let’s iZotope that” means let’s perform audio restoration on that clip and make it sound better.

I first came across iZotope at AES in 2012 and I’ve been using it ever since. Why? Because iZotope, version after version, keeps coming up with improved tools and new features that are so dang good it would be ludicrous not to update. In the past, it has been features like Ambience Match, Voice De-reverb, Spectral De-noise, De-plosive, multiple track audio options for VR and others. I have purchased almost every single version of RX Advanced, and I have never been disappointed. This is despite vowing each time that I will not buy the next version of RX Advanced and save a little money.

The most recent version of iZotope’s game-changing tool is RX 8 Advanced. In this COVID-19-plagued world, full of VOIP and Zoom calls, iZotope RX Advanced 8 offers an incredibly tantalizing module: Spectral Recovery. What is the promise of Spectral Recovery? According to the iZotope website: “Spectral Recovery helps restore frequencies above 4K that are removed when the audio is compressed for real-time streaming. Turn once-grainy, inarticulate recordings into crisp, clear conversations.”

How does it work in practice? Let’s take a look. Below is the spectrogram of a recording I got from VO artist Jason Katz in .M4A format. You’ll notice that the high end is “patchy.” The high-end is muffled, and the audio feels lossy/full of artifacts/a little dull.

Now take a look at it post Spectral Recovery:

It certainly looks a lot nicer. But how does it sound? Discernibly better! Does it sound like it was recorded in a studio? Absolutely not. Most notably, the artifacts remain. However, the high end is much more lively, and it feels a lot nicer in general. I have now tried this module against many different remote recordings and my verdict is as follows: Is this feature game-changing? No. Is it nice to have? Yes. Is it worth the upgrade cost? It depends.

For someone like me, who specializes in high-end audio restoration — absolutely. My clients are looking for any and every improvement possible. This delivers something quickly, that if possible before, was difficult to dial in. It’s worth every penny. For someone who just wants to edit and mix? Probably not. I still find that a basic EQ wielded properly will go further than Spectral Recovery in terms of making that Zoom audio sound better.

Features
Let’s go through the other features that were added.

• Guitar De-noise. Not that exciting for a non-musician, but it does work surprisingly well. That said, as with some of iZotope’s other modules, I’m able to achieve a very similar effect using some of the other modules already available in combination with each other.
• Music Rebalance. This tool is very impressive. I find, however, that unless you’re using it with a relatively light touch there is too much artifacting for it to be useable in a commercial project. That said, the small changes are transparent, pleasing andeasy to implement.
• Loudness Control (new GUI!). The old one wasn’t terrible, but this one is a little better.
• Wow and Flutter. This would have been really nice to have when I was dealing with more tape. It works surprisingly well (though I had to dig up an artificial example), and I think those who are in the archiving part of the industry will be happy to have it. That said, ironically, many filmmakers actually want wow and flutter in their sound tracks these days to make things sound more period.
• Horizontal Scrolling on Track Pad. I have wanted this feature forever. I don’t know why it wasn’t there earlier, but I’m glad it’s there now.
• Module Chain Improvement. Okay, this one makes me really happy. The module/batch processing in previous editions of RX was possible to use, but not great and I found myself avoiding it. This version of the Module Chain works the way that I like it to — add your modules, dial-in the settings, and save your preset. Viola!

Final Thoughts

RX 8 is not the heftiest of all RX updates (like the one that introduced Ambience Match) for post sound pros. However, it is a substantial update, and if you make your money editing and mixing audio for film, television and radio, I think it is worth the upgrade price. If you’re super low on funds, you could probably hold onto your copy of RX 7 a little longer and see what RX 9 has to offer.

As for me, I will be happily iZotoping away. I literally use RX on every single project that comes to me, and now I have one more tool to throw at the dreaded “Zoom Audio.”

Cory Choy is an Emmy Award-winning sound mixer and owner of Silver Sound.