As one of the less populated sectors of the audio processing market, the range of restoration and clean-up software available to today’s producer/engineer makes for a relatively straightforward shortlist. And what with the sale of erstwhile heavyweight players Accusonus to – of all companies! – Meta earlier this year, the field has narrowed even further of late. Here, then, are five of what we consider to be the very best options currently around for getting rid of noise and ironing out spectral kinks in your musical and other recorded material.

iZotope RX 10

If there’s an industry standard in audio restoration solutions, it’s probably iZotope’s action-packed software suite, RX. Now in its tenth full generation, this takes the form of a spectral audio editor stuffed with processing modules dedicated to eliminating unwanted noises of all conceivable kinds, dialling back excessive reverb, mending compromised voice tracks, repairing clicks and clipping, and much more. Naturally, plugin versions of most of those processors are also included for use in your DAW or other audio editor of choice, should RX itself not appeal.

The pace of development has slowed somewhat with the last couple of versions, but whether that’s because what’s already contained in the RX package is so comprehensive and powerful that adding to it is becoming an exercise in diminishing returns, or more down to iZotope shifting their focus to other products, is up for debate. Either way, though, RX 10 certainly remains a hugely enabling box of audio repair tricks for music production and post. Check out Mike Thornton’s in-depth RX10 review.

ACON Digital Restoration Suite 2

Taking a rather less expansive/busy approach to audio fix-up than that of iZotope’s cavernous resource, ACON’s nifty bundle sets its corrective sights on four specific aural irritants with the descriptively named DeHum 2 (mains and motor sounds), DeNoise 2 (hisses, buzzes and wind), DeClick 2 (vinyl crackle and digital dropouts) and DeClip 2 (analogue and digital clipping) plugins, all of which can operate in surround formats up to 7.1.6. The algorithms governing each processor are clever enough to get the majority of the job done on their own, but you get a good degree of manual control for fine tuning, nonetheless; and the dynamic profiling of DeNoise 2 is particularly noteworthy, doing an amazing job of nuking even the most mercurial of wind sounds. All in all, this is a really solid toolbox at a very fair price.

As an alternative to the complexities of Restoration Suite 2, those working only with dialogue recordings might want to take a look at Acon’s task-orientated Extract:Dialog, which essentially boils all of the above down to a single plugin built with the sole purpose of de-noising spoken word tracks.

CEDAR Studio Complete 9

Stepping things up several gears, CEDAR Audio’s restoration bundle is so jaw-droppingly expensive that you have to contact them via the website to get a price (spoiler: it’s about five grand), but as the long-standing go-to for serious movie and TV studios around the world, it’s operating on a whole other level to the rest of our entrants here.

Studio Complete brings together the 11 plugins of CEDAR’s Studio Restore, Studio DNS and Studio Retouch offerings, all of them based on the same technologies as the DSP-powered CEDAR Cambridge system and all-hardware DNS units; and we’re not overstating things when we say that there’s absolutely no noise or audible issue that, between them, they can’t resolve. Studio Restore consists of eight ‘elemental’ restoration plugins – Debuzz, Auto Dehiss, Declick, Decrackle, Dethump, etc; Studio DNS presents a pair of plugins (DNS One and Two) for dialogue noise suppression (see what they did there?); and Studio Retouch is the latest version of the legendary spectral editor that laid the groundwork for all those that followed. The magic, of course, lies in the algorithms, which reduce user input for many of the plugins to a single button or knob, and the quality of the results they all deliver is, well, literally Oscar-winning.

Okay, this level of restorative power is out of reach (and wholly unnecessary) for the vast majority of us, but when you need the very best that money can buy, CEDAR’s is the bundle to beat.

Waves Restoration Bundle

Once again, the names say it all with Waves’ venerable audio cleaning five-pack. X-Hum, X-Crackle and X-Click do exactly what they say on the tins, while X-Noise and the newer Z-Noise enable ‘static’ and dynamic noise suppression respectively. They’ve been around for almost two decades now, but despite that, every member of the Restoration Bundle manages to stay relevant thanks to the apparent durability of the algorithms at work and the intuitive, informative design of their interfaces. Highlights include X-Crackle’s frequency visualiser, X-Hum’s deployment of eight notch filters in doing its thing, and Z-Noise’s ability to extract a noise profile from any source.

The RRP on this one is utterly nonsensical given its age, but as is the way with Waves, the actual ‘sale’ price of the Bundle is far more reasonable.

Zynaptiq Repair Bundle

Coming at the subject of audio restoration from a completely different angle, Zynaptiq’s trio of futuristic plugins is geared up for the annihilation (or, indeed, emphasis) of reverb, high-frequency ‘chirping’ effects caused by audio compression and FFT processing, and unpleasant frequency resonances of all kinds. Unveil facilitates attenuating (or boosting) of reverberation within any signal via an AI-based engine; Unchirp employs ‘Musical Noise Reduction’ and ‘Dechirping’ algorithms to tidy up encoded signals without hurting their transients; and Unfilter basically ‘linearises’ the frequency response of the input signal to whatever extent you need. That really is putting it all in the simplest of terms, though: these are deep and involving plugins capable of pulling off truly extraordinary feats of sonic cleansing and alteration, and although they come with a bit of a learning curve, it’s one well worth negotiating.

With its hefty price tag, Repair Bundle certainly isn’t an investment anyone would take lightly, but the technological innovation behind it, and the unique effectiveness with which it does away with its target nuisances, make it a must-try for musicians and dialogue producers alike.

What’s your favourite restoration suite and why? Let us know in the comments.