With so many great free EQ plugins to be found online, how do you know which are worth your investigative time? You don’t, which is why we’ve boiled them all down to what we reckon might just be the five best…

Blue Cat Audio Triple EQ

Comprising high and low shelving bands and a parametric mid band, Triple EQ is designed to operate like a filter with a limitlessly adjustable shape. The gains of the two shelves at 20Hz and 22kHz are adjusted using the handles on the left and right of the graph display, while dragging the central node adjusts their corner frequencies, as well as the centre frequency and gain of the mid band, thereby, indeed, making the whole thing feel like a single complex filter. The width of the parametric band is separately adjustable (mousewheel or knob), and the gain of the response curve can be offset or switched to automatically peak at 0dB.

It’s a nifty setup that works well for both ‘musical’ and surgical equalisation of instruments, busses and mixes, and coming from the mighty Blue Cat, the sound and response (it’s zero-latency) are second to none. It also installs in Mono, Stereo and Dual versions, the last separating the two stereo input channels for independent left/right or mid/side adjustment.

Tokyo Dawn Records NOVA

Pushing the boundaries of what can be expected from a free equaliser, TDR’s incredible plugin would be well worth the download just for its four parametric/shelving bands (10Hz-40kHz), low- and high-pass filters, and easy interactive display. But the icing on NOVA’s cake is the implementation of dynamic EQ – that is, per-band envelope following gain modulation, tracking the input signal or an external sidechain – which really does put it in a class of its own in the free arena, as far as we’re aware.

Each band can be switched to dynamic mode independently of the others, so you can freely mix regular and dynamic processing in a single instance of the plugin, and the possibilities this opens up are broad and empowering: multiband compression, de-essing, clamping down on problematic resonances, etc. You can also switch the whole thing into Wide Band mode for use as a compressor, excluding selected frequency ranges from processing to leave their dynamics unaffected.

No doubt about it, NOVA is a must-have EQ for mixing, mastering and sound design, and should you find yourself wanting even more from it, you can upgrade to the Gentleman’s Edition for €60, adding two further bands and various extra functions.

Melda Production MEqualizer

Another stellar EQ that far exceeds the connotations of its non-existent price tag, MEqualizer (which comes as part of Melda’s MFreeFXBundle) gives you six bands of frequency-shaping, with ten filter types for each band: Peak, Low/High Shelf, Low/High-Pass, Band-Pass, Notch et al. Conventional stereo and mid-side channel configurations are catered to, tube saturation can be dialled in for authentic analogue flavour, and the Harmonics panel is an interesting inclusion, enabling both corrective and creative tweaking of harmonics above the selected band to an extraordinary level of detail. Visualisation comes in the forms of a spectrogram and a sonogram, and the interface is bristling with all the standard Melda niceties – MIDI learn, A/B switching, randomisation, etc.

It’s not that long ago that Melda (or anyone else) could have cheerfully charged 100 quid for a plugin of MEqualizer’s specification and calibre, so the fact that it costs nowt is truly remarkable. Go get!

Ignite Amps PTEq-X

If you’re not already sorted for Pultec emulations, you might as well put your wallet away and give Ignite Amps’ very serviceable gratis take on the concept a go. Racking up virtual PEQ-1A, MEQ-5 and HLF-3C equalisers in a single plugin to replicate the originals’ intended use as a unified EQ solution, PTEq-X deploys individual component modelling to achieve a very compelling recreation of that legendary Pultec vibe, and expands on the original design with a few extra frequency options on each of the PEQ-1A bands, and “refined” precision in the MEQ-5 and HLF-3C filters. There’s also an optional tube saturation stage with four fantastic sounding tube models to choose from, and 2x oversampling for the reduction of aliasing at the expense of CPU cycles.

Ably capturing the musicality and mojo of the three passive EQs that inspired it (PEQ-1A ‘low end trick’: check!) and successfully bringing them together in combination, PTEq-X really does hold its own against the commercial competition and could genuinely be all the Pultec you need.

Photosounder SplineEQ Free

Now a decade old but still unique in its approach to frequency sculpting, SplineEQ is a linear phase EQ that does away with conventional filter types, instead facilitating the creation of extremely precise and detailed cubic Bézier spline response curves via the manipulation of up to 60 nodes. Reducing that number to four, SplineEQ Free gives you a taste of the possibilities offered by the full version, but also stands as a powerful equaliser in its own right.

The titular spline curve is shaped by dragging around the aforementioned nodes and adjusting their ‘tangent handles’, and how tightly the actual curve (dotted line) adheres to the mathematically perfect curve (solid line) is governed by the Resolution control. Up to +60dB of gain is on tap, the frequency and gain of the whole curve can be shifted using the Transpose and Overall Gain controls, and the Gain Scale knob squashes or stretches the curve on its Y axis. Behind all that, the brilliantly conceived display uses colour intensity to represent the volume level across the spectrum, showing the pre-processed level below the curve and post-processed above it.

Much more than just a technological curio, SplineEQ Free’s radical and unashamedly geeky approach to equalisation is made wholly approachable by its intuitive interface and enjoyable workflow. Good for workhorse EQ duties, but also brimming with creative potential, it’s simply got to be done.

Does your plugins folder feature any notable free EQs? Let us know in the comments.