IZOTOPE RX 7
The innovations just keep on coming with the seventh generation of this ever-expanding spectral editing and audio restoration suite
In 2016, version 6 of iZotope’s spectral audio editor and repair/restoration plugins suite (VST/AU/AAX) introduced machine learning to its technology base alongside a range of miraculous new modules, including De-wind, De-noise, Mouth De-click and De-rustle. Like every version before it, it scored 10/10 in 245.
RX 7 adds a handful of new modules, as well as an ‘Assistant’ of the kind found in iZotope’s other flagships, Neutron and Ozone. We’re looking at the top-of-the-line Advanced version here, but there’s Standard edition (£299), which loses multichannel functionality and various dialogue-related modules, and RX 7 Elements (£99), which is decidedly lighter, feature-wise. See the iZotope website for a full comparison and upgrade pricing.
You’re surrounded
With RX 6, our only real complaint concerned the software’s continued lack of support for multichannel audio, but we can happily report that this has been addressed: RX 7 Advanced supports multichannel processing up to Dolby Atmos 7.1.2. Channels can be viewed and edited separately or collapsed down to a group for collective processing. Very nice too.
Given recent iZotope history, there was no way RX 7 wasn’t going to get an automated helper of some sort, and Repair Assistant (all editions) is geared up for automatic fixing of sub-par recordings. An integrated function of the audio editor, rather than a module, it specifically does away with clipping, clicks, hum and noise, in three source material modes: Dialogue, Music and Other. With your audio region selected, clicking the Start Analysis button ‘intelligently’ creates three corrective processing chains (or three variations on a single chain in the Standard edition) using the appropriate modules (De-noise, De-click, De-hum, etc), presented as ten-second previews with unhelpfully tiny spectrograms. The specifics of each chain are revealed by hovering the mouse pointer over them, and the chains themselves are accessed for tweaking, if necessary, at a click. With RX 7 Advanced, lowerand higher-intensity versions of each chain can also be generated, and each of the four ‘issues’ can be bypassed in the Preferences if not
“Given recent iZotope history, there was no way RX 7 wasn’t going to get an automated helper of some sort”
needed. How successful Repair Assistant is depends entirely on the nature of the source material. With dialogue, it almost invariably does a great job, which shouldn’t come as a surprise given the fairly rudimentary nature of the problems it addresses. With musical material, things are less clear cut. Clipping, hum and noise are well handled, but you might want to disable click detection, as it sometimes attempts to kill ‘clicks’ that are actually percussive transients in the source material.
Repair Assistant is a solid timesaver. Given that it’s just setting up the existing modules for you, however, it doesn’t offer anything qualitatively ‘new’ in terms of end results.
Talking therapy
On to the new modules, then. First up, Dialogue Contour (Advanced only) is essentially a multi-breakpoint pitch modulation envelope optimised for spoken word material. The waveform and spectrogram of the region currently selected in the audio editor appear in the module, where nodes are added and moved around to apply pitch inflections over time, with the Formant Scaling slider compensating for any unnatural sounding changes in timbre. Dialogue Contour doesn’t wow us – its usable range, before obvious artefacts start to creep in, is so short that only very minor intonation adjustments are really viable.
A more targeted version of the established De-reverb module, Dialogue De-reverb (Advanced only) uses machine learning to melt reverberation away from spoken word recordings. Applied as an offline process (with Reduced Quality preview), it’s very effective, although as with all dereverberation processes, its effectiveness largely depends on the depth and tail length of the ’verb. The Ambience Preservation control proves useful when the algorithm misinterprets desirable background noise (traffic, crowds, etc) as reverb, though.
The Variable Time and Variable Pitch modules let you draw independent timestretching and pitchshifting envelopes along the timeline, just like Dialogue Contour, with controls for reducing ‘phasiness’ and preserving transients. Like the ‘static’ Time & Pitch module, these are applied and auditioned offline.
Lastly, Pro Tools users will no doubt enjoy the AudioSuite versions of De-rustle, Dialogue Isolate and Music Rebalance (see The music sounds better with you), enabling those modules to be employed (albeit offline, of course) directly in their DAW. And De-rustle and Dialogue Isolate can now be previewed without having to use the Compare dialog, again at lower quality than you get from the final render.
As an upgrade from v6, RX 7 would score 8, losing points for the narrow operational range of Dialogue Contour and the fact that half of the new stuff only comes with the Advanced edition. But Dialogue Contour is just one module of many, and given that RX 6 would still be a clear 10 had RX 7 not come along, we’d definitely award its successor the usual full marks as a solo proposition.
“It confidently handles total isolation or removal of those track elements, too – remixers will love it”