Gear Reviews

Eventide Split EQ Review: Get Creative & Open Up New Musical Possibilities

SplitEQ offers a new approach, featuring what Eventide calls a 'Structural Split engine' that divides incoming audio into separate transient and tonal streams feeding 8 bands. The result is a highly innovative EQ design for both corrective and creative EQ applications.

Eventide has a rather amazing history and holds a special place in analogue studio mythology, with its range of harmonisers from the ‘70s and ‘80s. More recently, the company brought these legendary units back to life in plugin form with a few added bells and whistles, designed to bring them up to date for the digital studio engineer. One thing has remained apparent, and that is the unique range of quality audio afforded by these plugins. So while they remain at the higher end of the market in terms of price, this also reflects their unique status and the esteem in which they are still held.

When Eventide released the Clockworks bundle, featuring the Omnipressor, H910, H949 Instant Flanger and Phaser and the SP2016 Reverb, they brought all the legends together in one unique package, giving you a range of sounds you just won’t find anywhere else. The company also has an excellent reputation for exceptional audio quality, while not being processor intensive!

Two Sides to Every Storey

For me, it was a treat to be asked to have a play with Eventide’s new SplitEQ plugin. The very concept is fairly unique and, at the point of putting pen to paper, I’m not aware of anyone else doing anything similar. However, I don’t profess to know everything, and it seems that every day brings a new plugin of some description.

So what is SplitEQ? Quite simply, it’s two EQs in parallel. The incoming signal is split into its Tonal and Transient elements using Eventide’s patented Structural Split. It then passes through the parallel EQs, one acting in a conventional way on the tonal source signal and the second on the transient element of the source. They are then combined at the output. This allows you to adjust transient or tonal signals independently or together.

Immediately you can see a whole host of possible applications for the SplitEQ. Two common examples are, you want to add some air to the mix but you want to avoid increasing sibilance. You can increase the tonal element of the top end but leave the transients where they are, or possibly reduce them slightly if sibilance is creeping in.

Alternatively, you want to increase the weight of the kick drum but don’t want to simply add a low shelf boost, as this will muddy the sound, so just add the low shelf boost to the transient signal - immediately you have a more potent kick drum with none of the headaches. If you want to hear some of these ideas in action, check out the Eventide SplitEQ Video on our YouTube channel ‘Headliner Hub’ for examples of the above, along with a few other ideas.


A quick glance at the interface reveals eight bands of processing, the two extremes of which are by default high and lowpass filters, but the other six offer low/high shelf, peak, notch, tilt or bandpass filter types per frequency. Although each band is sweepable to a set frequency for both the transient and tonal splits, all other parameters are completely independent, so you could have a transient boost with a completely different Q to that of your tonal cut at the same frequency for example.

Again, by default the Q for each band was set at 1.0, but by simply moving the mouse over it, it splits into a Green and a Blue 1.0, allowing you to either click and type in a value or click and drag up and down to the desired value. The significance of the Green and Blue immediately becomes apparent, as all Transient processing is represented in Green and all tonal Blue. This is further emphasised by the master control section on the right, which has a Green and a Blue fader for each of the split EQ characteristics and allows you to really pull your mix apart to see what sits up and what gets lost. A real handy and very necessary master section.

On the right, below the master Transient and Tonal faders, is a value box for each should you find dragging the faders up and down a chore. I thought the calibration and ability to drag stuff about and hit precise values was excellent and probably quicker than typing in the values, but the option is there. Below that is a pan value, which would ordinarily be left at C for centre, but you can drag your master processing focus for either the transient or tonal processing off centre should you wish.

Below that is an EQ scale control, which by default is at 100% but you can roll this back if you wish. In doing so, it slowly rolls back the level of processing you have applied, in essence behaving similarly to parallel processing where you are letting an increasing amount of the source signal through.

Below that is a bypass section that gives you the option of a global bypass for the plugin or just the EQ section. And finally, below that are a number of options for the Analyzer, which gives you a graphical representation of your audio in the GUI, and with pre and post option buttons you have a handy visual guide to the original and affected audio.

This is an exceptionally user-friendly plugin, which sounds wonderful and is surprisingly moderate in its CPU usage.

In the top right hand corner of each of the band information boxes is a headphones icon that brings up a further three icons - Green, White and Blue - when you hover over it. This allows you to hear in isolation the effect of your processing choices in each band, and although the Green transient selection can sound a little darker, this is fairly common in other transient design tools and is very much what you will hear when you're attempting to isolate transient information. For an overview of the full frequency range of the transient or tonal elements of your audio there is a further headphone icon on the right side of the bottom panel that you can select, which then splits into a Green and Blue icon and you simply click the one you want.

Panning Transients

Now we come to the really clever part. Along the bottom panel are the EQ and PAN options, by default EQ is selected but if you select pan the boxes change to provide a transient and tonal balance control. Now you have a set of controls with which you can shape your audio within the stereo sound stage, providing you another dimension of control. By selecting an EQ band and dipping the transient off centre in the area of the overly aggressive Tambourine, you can hold it back, making it part of the performance rather than a feature. I actually had a lot of fun playing with some well known songs just to see how manipulation in all the dimensions this plugin offers could have solved issues that at the time were left to creative licence.

Following on along the bottom panel is a small menu button next to the SPLIT heading, which gives you a selection of different algorithms for detecting and making the split for different instruments. By default it is on full mix but there are a number of algorithms for drums, acoustic and electronic, as well as bass, piano, guitar and vocals, so there is very much a focus on this plugin being a mix tool as well as a mastering tool.

Following on from the Split algorithm is a Transient percentage, which by default was at 50% but I found when I increased the percentage I got much sharper transients when they occurred but less of them. In isolation, they sounded very metallic and unnatural but conversely gave the most dynamic and alive sound when brought together with the tonal alterations. Likewise, reducing the Decay time also helped to focus how long the transients stayed present. Lastly, Smooth - in milliseconds - is the smoothing period of transition from transients back to the tonal regions.

Along the top is the familiar undo/redo, a comprehensive range of factory presets, A/B buttons, a link for a very comprehensive user manual, which I’ve only just found, and a dB scale selection for the GUI. Of course, there’s also a save and recall facility for creating your own presets, which can be recalled in the various different formats of this plugin.

This is an exceptionally user-friendly plugin, which sounds wonderful and is surprisingly moderate in its CPU usage. To try to emulate what this plugin does in one instance you might need to employ a pretty high quality EQ and possibly a number of instances of a good transient designer. While it’s clearly an excellent high-end mastering tool, its range of presets and the inclusion of selectable algorithms for transient detection would suggest this is far from being a one trick pony.

Eventide SplitEQ is available soon in all the usual formats, so head over to the company’s website and check it out.

You can also check out our full video demonstration of SplitEQ, here.