Best freeware plug-ins: Six best free mastering tools

We’ve rounded up six of our favourite plug-ins for mastering that won’t cost you a penny.

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Six best free mastering tools

Traditionally, when one thinks of a mastering suite, it’s common to imagine a pristine console room racked out with high-end compressors, limiters, EQs and acoustic treatment that is unattainable to mere mortals. The truth is, even the mastering engineers at Abbey Road Studios are working in-the-box, as we found out recently.

So why can’t you? And why should it cost an arm and a leg? Well, perhaps you can, and perhaps it doesn’t. Here are six of our favourite freeware mastering tools that can help you add the finishing touches to that brilliant mix of yours.

The best freeware plug-ins for mastering at a glance

  • Youlean Loudness Meter 2
  • A1StereoControl
  • Noiz-Lab LE Mastering Bundle
  • Klanghelm IVGI
  • Vladg Sound Limiter no.6 – Multiband limiter
  • Xfer Records OTT

Youlean Loudness Meter 2

youlean loudness meter 2

Although not the most exciting plug-in you’ll have in your arsenal, Youlean Loudness Meter 2 is more essential than you might think. Giving you measurements in LUFS, Loudness Range, Dynamic Range and True Peak, you’ll be able to ensure that your audio is fit for playback on a range of platforms. Youlean Loudness Meter comes preloaded with presets for film, TV, and video games, so you won’t be required to do your homework to find out your boundaries. Of course, if you wanted presets for different music streaming services like Spotify, Deezer and Apple Music, you’ll have to move up to the Pro version.

Youlean Loudness Meter 2 also has an attractive, scalable GUI, which is much desirable for paid plug-ins, let alone a free one. You can analyse your track within seconds, A/B different measurements, and even export a graph of your track to PDF. It’s available as VST2, VST3, AU and AAX for both Windows and macOS.

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Stereo expansion is often used in moderation during the mastering stage to give tracks more width and depth across the stereo field. A1StereoControl gives you precise control over your imaging, with Mid/Side monitoring, phase flipping, and a selection of algorithms for pan curves.

Although width is warmly welcomed in audio, the lower end of the frequency spectrum is often best left in the centre. A1StereoControl lets you keep your bass pumping through the left and right sides equally with the Safe Bass button. Upon activation, all frequencies under a user-defined threshold are locked to the middle. Of course, the aesthetics of the plug-in aren’t the most contemporary, but when you’re paying sweet nothing, it’s easy to glaze over this drawback. You can get this in VST, AU and AAX for Windows and macOS.

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Noiz-Lab LE Mastering Bundle

Noiz Lab LE2

Accompanying The One Hour Mastering Workshop book from Home Studio Mastering is the Noiz-Lab LE Mastering Bundle. This clever little bundle contains five plug-ins that you can master your whole project with. It’s comprised of a limiter, compressor, EQ, Monomizer and Convolver. It’s a fairly basic collection, but is ideal for grasping the foundations of mastering and they’re sure to come in handy at some point for producers of all levels.

Nifty features like Mid/Side modes on the EQ and different algorithms on the compressor open up some satisfying options for you in the mastering stage. The bundle is available in VST, VST3, AU and AAX format for macOS and PC.

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Klanghelm IVGI

Klanghelm IVGI

One of the perils of producing music in the digital domain is the clean and clinical sound resulting from computerised processing. The imperfections that came with recording to tape often provided colouration that is now desirable, and often emulated, in 2020.

Some people try to reintroduce this warmth by adding saturation at the mixing or mastering stage. IVGI reacts dynamically to the input signal and can produce subtle saturation when applied to a master signal. It can also be used to distort tracks. The Controlled Randomness feature introduces drift and variance, and lets you alter the frequency dependency of the saturation with the response control. It’s available as an AU, VST, VST3 and AAX plug-in for macOS and PC.

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Vladg Sound Limiter no.6 – Multiband limiter

Vladg Limiter 6

Limiting generally comes at the end of your mastering chain and is the last stage in processing a track. Although your DAW may come with a limiter, it could be pretty basic, and Sound Limiter no.6 offers more options – all for free. Moreover, despite its age, we’ve found it still to be one of the best freeware limiters out there.

There are five modules: an RMS compressor, peak limiter, high-frequency limiter, clipper and a true peak limiter. Brickwall and soft limiting are supported and use different timing settings depending on the effect you want. Mid/Side is supported, and there’s a multiband mode for more precise control over the limiting of different frequency bands. 4x oversampling is available, and you get retro level meters, plus a choice of two GUIs. no.6 Compressor is available in AU and VST2 for macOS and PC.

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Xfer Records OTT

OTT Xfer Records

Xfer Records, the brainchild of deadmau5 and Steve Duda, has a selection of plug-ins that have become favourites for many producers in a range of genres. OTT is the brand’s freeware multiband compressor, which is actually a combo of two separate compressors each with three EQ bands. In a lighthearted quip, it’s been referred to by some in the music tech community as a “sound-goodizer”. This is likely due to the effect it has on higher frequencies, brightening the overall sound of a track.

It features upward compression and downward compression, with a depth control knob to adjust the amount of applied compression. The Time knob is a swift way of adjusting attack and release times, and the visual reference on the plug-in gives you realtime feedback on how the sound is being affected. The only real downside is a lack of more in-depth features – but that’s possibly why so many producers gravitate towards it. Sometimes, less is more.

You can get OTT in AU, VST2, AAX for macOS and Windows.

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WaveLab Elements

WaveLab Pro 10This particular mastering tool won’t be free forever, but Steinberg is offering out 60-day licenses for WaveLab Elements, its comprehensive mastering suite. WaveLab Elements can give you a fresh perspective on your mix, as you’ll be using an entirely different platform to finish the job, rather than your DAW. With 18 VST3 plug-ins at your disposal, including Compressor, Gate, RoomWorks SE, iZotope MBIT+ Master Dither, Tube Compressor, Resample and more, there should be plenty of utilities here to get your track sounding its best.

You’ll also have some access to tools like the Audio Montage, Audio File and Podcast environments, as well as full video playback support. You’ll be limited to three audio tracks per project, and there certainly are limitations to this suite, including the fact it’s only a 60-day license. But WaveLab Elements is a platform that can give you a taste of in-depth mastering and achieve professional results.

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Get to grips with mastering with our guides and tutorials here.

For more freeware click here


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