iZotope RX 12’s focus on improved accuracy and quality pays offElements: $99
Standard: $399 (update from RX 11 Standard $129)
Advanced: $1399 (update from RX 11 Advanced $269)
iZotope.com
Despite impressing me upon its launch in May 2024, RX 11 had already gained a patina of age bycthe turn of the year thanks to the ever-growing crop of machine-learning-based audio tools hitting the market.

READ MORE: Steinberg’s new SpectraLayers 12 has “a strong focus on the needs of the post-production industry”

Steinberg SpectraLayers Pro is RX’s closest competitor — it quickly trumped RX 11 with its own v11 release in June 2024, followed a year later by the even more impressive Pro 12. Also, given one of RX’s biggest draws is its stem-splitting tools, the growth and quality of services such as LANDR Stems and LALAL.AI, not to mention native stem splitting within DAWs, had made RX 11’s stem splitting look – and sound – increasingly tardy in comparison.
This left users wondering how and when iZotope was going to respond, and what that response would look like. Well, wonder no more because RX 12 is here. Is there enough in the update for it to regain its premiere position? Let’s see…
Image: Press
What’s new in iZotope RX 12?
The obligatory user interface update expected of all software updates is, in RX 12’s case, fairly subtle. So much so that one aspect flagged by iZotope – namely a larger spectrogram – is so marginal that I wouldn’t have noticed had it not been pointed out. Nevertheless, features such as an ever-present monitor volume slider, resizable History panel, and a small reworking of the colour palette, make for a pleasing refresh.
I’m more interested in the consequential stuff, though, and here there’s a lot more meat on the bones…
The majority of processing modules now offer difference (delta) monitoring/processing, which reverses what is output from the module. For example, with Dialogue Isolate, engaging difference processing means the dialogue will be removed from the audio, leaving background noise. While this is handy as a way of extending the functionality of modules (sticking with the example, Dialogue Isolate also becomes Background Foley Isolate!), it’s perhaps most useful when configuring module parameters, making it easier to judge the impact of those parameters.
Moving to specific modules, there’s an all-new Trim Silence processor that’s particularly useful when editing podcasts, voiceover tracks and field recordings, making it easier to move between sections of dialogue (or whatever you’ve recorded) during editing. It’s a big time-saver too and, unlike stripping silence in a non-destructive environment like a DAW or NLE, Trim Silence produces entirely new – and often much smaller – audio files, and so can significantly reduce the total file size of a project.
Trim Silence in iZotope RX 12. Image: Adam Crute
Machine learning enhancements in RX 12
Of course, RX’s biggest attractions are its various machine-learning-powered rebalancing and separation modules. New here is the Scene Rebalance module, which does for video production what Music Rebalance does for music production. The new module recognises dialogue, music and effects, allowing the volumes of these elements to be rebalanced in-place or split into separate audio streams. This it does with an impressive degree of accuracy and a minimum of audible artefacts. Moreover, as with all of RX’s separators, Scene Rebalance is 100% lossless – that is, if you separate a source and play it back alongside a phase-reversed copy of the original audio, all you hear is silence. Unfortunately, Scene Rebalance is only included in RX 12 Advanced, the pricing of which I’ll return to later.
Music Rebalance and Dialogue Isolate, whose results had not kept up with those of competing stem separators, now deliver markedly higher quality than previously – as convincing as any I’ve heard! I’m somewhat disappointed that Music Rebalance can still only recognise vocals, drums, bass and ‘other’, but this is because iZotope’s focus was on improving the quality and accuracy of separation in RX 12, something it’s achieved effectively. Extended instrument recognition is very-much on RX’s development roadmap, however.
Scene Rebalance in iZotope RX 12. Image: Adam Crute
The De-bleed and Breath Control modules have both received ground-up rebuilds to embed ML-based features within them. In De-bleed’s case, this allows the module to automatically isolate a variety of common sources from the mic-bleed captured from other instruments, thereby saving you from having to train the module yourself (although this mode is still available). With Breath Control, machine learning makes for a far faster setup, and much more accurate recognition and removal of unwanted breath sounds than previously. Once again, the classic operation mode is still available for those who want to use it.
Alongside improved results, the overhauled ML processing is noticeably faster than previously, even when operating at the highest quality level. For example, splitting a 4’30” test mix in RX 11 took around 2’30”, but the same task in RX 12 took around 1’45”. The results sounded significantly better too. Not only does this mean less thumb-twiddling, it’s also allowed Music Rebalance and Dialogue Isolate to join the suite of real-time RX plugins that can be used natively in a DAW. Nice!
De-bleed in iZotope RX 12. Image: Adam Crute
Stems View
Another common gripe about RX’s stem splitting has been that separated stems are opened in their own tabs. Playback of those tabs could of course be synchronised, but editing meant a lot of fiddling and switching between different screens.
RX 12 addresses this with a new Stems View that displays stems as lanes within a single tab. Lanes can be muted and soloed as needed, and selections – both time and frequency – affect all lanes simultaneously. When you need detailed control over a single stem, you can select that stem from a dropdown menu to switch to a standard full-window view of the audio. Not only is Stems View infinitely better than how previous RX versions handled things, it’s more natural and intuitive than the approach taken by SpectraLayers.
Stems View is also massively useful when working with RX as an ARA plugin in your DAW. Annoyingly, though, RX 12 still only supports ARA in Apple Logic and PreSonus Studio One 7 / Fender Studio Pro 8. Extended ARA support is on iZotope’s to-do list, though.
Stem Split View in iZotope RX 12. Image: Adam Crute
What’s the difference between the different RX 12 editions?
As previously, RX 12 comes in three editions. Elements is the most affordable, providing a set of six RX plugins for use in your DAW, although the standalone RX audio editor and modules are not included. Elements is useful for dealing with common problems like clicks and hums, and includes the Repair Assistant that combines various types of corrective processing into a single plugin.
RX 12 Standard is solid value, including the standalone editor and the vast majority of RX modules along with their plugin counterparts. It only lacks the processors and modules aimed at TV and film post-production – Scene Rebalance, Ambience Match, and so on.
These additional modules are only found in RX Advanced, but are they really worth an additional $1000 over the cost of Standard? They’re impressive tools, for sure, and aren’t widely useful in a music production context, but they are useful to podcasters, streamers, independent filmmakers, and many others who wouldn’t have access to the big studio budgets this pricing assumes. Given that RX isn’t the only rooster in the henhouse, this premium may be costing iZotope sales.
Nevertheless, Advanced is an incredibly powerful proposition, as is RX generally, and this latest version is a big step up from its predecessor. There remain some gaps in its capabilities compared to competing systems, such as the limited number of stem types recognised by Music Rebalance, but RX is very much back to the top of its game.
Image: Press
Key features

Spectral audio editor with advanced processing modules
Many processing modules included as plugins (AU, AAX and VST3 formats)
NEW Scene Rebalance, Stems View and Trim Silence
REBUILT De-bleed and Breath Control
IMPROVED Music Rebalance, Dialogue Isolate, Difference (delta) monitoring and processing, user interface and workflow
Requires macOS Sonoma (14.7.x) and upwards; Windows 10 (22H2) or Windows 11 (24H2)
ARA plugin compatibility with Apple Logic Pro and PreSonus Studio One 7 / Fender Studio Pro 8

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