Solid State Logic’s 4K E is a near-perfect plugin emulation of a classic mixing console

The groundbreaking SL4000 E channel strip has been plugin-ified many times over, but this offering from the console’s original creators promises to be the best yet

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Solid State Logic 4K E

Solid State Logic 4K E

Review Overview

Our rating


Our verdict

Near-perfect recreation of the SL 4000E’s channel strip
Gain-compensated model of original Jensen preamps
Switch between all three varieties of SL 4000E (Brown, Black or Orange)
Includes model of original DBX fader for increased sonic authenticity
Easily re-order the signal path or switch modules into sidechain path
Full SSL 360° controller support; complete integration with SSL UC1

Full price perpetual licence is quite expensive

$329 / £263.99 (perpetual licence) / as part of SSL Complete Bundle from $14.99/month,

Take any hit record from the 80s or 90s and, the chances are, it will have been recorded and mixed on a Solid State Logic SL 4000 (or 4K) console. The first commercially available units were 1976’s SL 4000B, which introduced the world to flexible routing, fader automation and built-in tape transport control. But it was the arrival of the SL 4000E, three years later, that saw the 4K become the must-have mixer for professional studios the world over.

The 4K E improved on the 4K B’s innovations, adding features that maximised recording quality and improved workflows. The most notable of these were the per-channel dynamics processing and a new four-band EQ setup that is now the standard across all professional mixing desks and DAWs.

With such a peerless pedigree, it’s no surprise that so many plugin developers have emulated the SL 4000 E’s channel strip — SSL included. With the British company now releasing an updated emulation of its hardware, we wonder if this could finally be the definitive 4K E model.

Solid State Logic 4K E
Solid State Logic 4K E

How do you use the SSL 4K E?

SSL 4K E starts with the mic preamp section although, being a plugin, this operates differently to the analogue preamp of the console.

The plugin provides a trim control for adapting the input track/signal’s level, along with an optional Preamp switch that, when enabled, introduces a model of the Jensen T-115K-E transformer found on the earlier 4K E. A knob is then used to adjust the amount of drive and colour delivered by the preamp model. Handily, the Preamp knob is gain-compensated, so cranking it up reduces the overall signal level by the same amount, making it easy to experiment with different intensities of drive and colouration without being influenced by level changes.

Solid State Logic 4K E
Solid State Logic 4K E

The mic preamp model is rounded off with the same high pass and low pass filter section found on the original hardware. This is followed by the EQ section, which provides the nowadays-standard arrangement of two sweepable parametric bands along with high and low shelving bands.

There were three different EQ circuits used in different variations of the 4K E console, and these are known by the colour of the knob caps used for the low-frequency controls: There’s the original, warm-sounding 02 Brown; George Martin’s cleaner, 242 Black with its wonderful low-end detail and punch; and the 132 Orange, a passive EQ design included on only a handful of consoles.

SSL has modelled each of these EQ circuits for the plugin, allowing you to easily switch between them (and see the colour of the low-end controls change at the same time!). All have a classic ‘British’ EQ sound and have an intrinsic musical quality, but each has a distinctly different character too so it’s really useful to have all three within the one plugin.

Dynamic routing

One of the SL 4000E’s biggest innovations was the inclusion of dynamic processing on every channel, made up of a compressor and a gate/expander. Unlike a dedicated outboard processor, SSL’s channel processors are relatively basic in design and operation, but deliver a great sound that’s perfect for conditioning and controlling incoming signals.

The plugin’s model of these dynamics processors is excellent, and has been enhanced with the inclusion of a handy wet/dry mix setting for the compressor. We also suspect there’s some lookahead wizardry going on with the expander/gate, given that it responds even better than the original hardware — never cutting off the tiniest smidgen of a transient when the signal level crosses the threshold.

The standard post-preamp signal flow of filters to EQ and then dynamics is ideal for most circumstances, but the plugin nevertheless allows that signal flow to be modified. Not only does this let you change the order of the different sections, but it also allows you to switch the filters and EQ modules from the main signal path and into the sidechain path. Here they can process either the normal internal sidechain or an external one that you feed to the plugin.

At the end of 4K E’s strip lies the fader and, for the stereo version of the plugin, pan and width controls, the latter being a mid/side balance adjustment. The fader is no mere output level control but a model of the DBX 202 Gold Can VCA fader used on 4K consoles, and this adds another layer of subtle yet authentic SSL character. The fader is coupled to an output level trim control, meaning you can push the fader into its amplification range (beyond the 0dB mark) and take advantage of the resulting drive and colouration, yet still maintain a balanced, clip-free output level.

Solid State Logic 4K E
Solid State Logic 4K E

What is SSL’s 360° platform?

The plugin works fine if using a boring ol’ mouse to interact with it, but the sharp-eyed amongst you will have noticed that the appearance and layout of the 4K E plugin bears a striking resemblance to SSL’s UC1 controller. This is no coincidence or lack of imagination on the part of SSL’s designers!

The 4K E integrates deeply with SSL’s 360° Plugin Mixer ecosystem, in particular the UC1 whose rotary controllers match exactly with the layout of the plugin. Throw in a UF1 or UF8 DAW controller and you can have direct control over the plugin’s fader too. It’s about as close as you will come to the sound and feel of an SL 4000E console without actually buying one. In the absence of a UC1, the UF1 or UF8 can control the entire plugin in the same way as they do any other plugin.

If you own any of these controllers then you qualify for a 70 per cent discount on the price of a perpetual licence for 4K E, making this a very affordable plugin that you’d, frankly, be foolish to overlook. The plugin is included in the SSL Complete subscription bundle too, which starts from $200 for an annual subscription, which isn’t much to pay for such a large collection of top-tier plugins.

A full-price perpetual licence for 4K E is expensive, though, and other SL 4000E plugins are more affordable. However, few – if any – are as accurate and well-featured as SSL’s plugin, so if you want to capture the hit-making sound of this legendary console, the SSL 4K E is the perfect way to do so.

Key features

  • Channel strip plugin (AAX, AU and VST)
  • Windows or macOS (Apple Silicon native)
  • High and low pass filters
  • 4-band EQ: two parametric bands plus low and high shelving bands
  • Dynamics section features compressor and expander/gate
  • HQ mode for advanced oversampling
  • Undo/redo

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