While, of course, just about any compressor can be drafted into service for group or mix bus control duties, when you want to really gel those disparate elements with maximum collective solidity and musical coherence, a plugin designed specifically for the job is always going to be the better option. With that in mind, here are five of the very best virtual analogue bus compressors you can treat your mixes to today.

Cytomic The Glue

Cytomic’s SSL bus compressor emulation plugin aims to nail the titular cohesion-inducing effect of the real console deal – that, in this case, being a hybrid of the modules from the E and G Series – and expands on it with various new features. All the expected parameters are in place – 2:1, 4:1 and 10:1 Ratios; fixed Attack and Release settings with an ‘Auto’ option for the latter – and it’s all perfectly straightforward and easy to get to grips with. As for the new stuff, The Glue boasts a few extra Attack and Release time settings, as well as a high-pass filter on the sidechain and a peak clipper. The most transformative additions, however, are the Range and Wet/Dry Mix controls, the first limiting the depth of compression for character modification, and the second enabling ‘New York style’ parallel compression.

On the mix bus, The Glue proves itself to be an impressive SSL-alike, pulling projects together nicely, and thanks to the Range control, it’s also thoroughly viable for compression of individual instruments. At this price, it’s a serious contender for any producer’s cash, assuming that famously ‘SSL’ sound appeals, natch.

PSP BussPressor

Clearly influenced by SSL’s general design ethos but not aping any particular real-world model, PSP’s acclaimed VCA-style compressor does a great job of tightening up group busses and the master out, with a character and flavour all its own. The Ratio, Attack and Release controls all snap to fixed values, from 1.5:1 to 10:1 in the case of the first, and 0.1-100ms and 0.1-3s or ‘Auto’ for Attack and Release, respectively; and there are separate Dry and Compressed level controls for parallel processing. The sidechain signal can be filtered and blended between internal and external source signals, too, which isn’t something you come across every day.

Another competitively priced option, BussPressor is one for those who want SSL-style functionality in their bus compressor, but not necessarily an overtly SSL-style sound.

UAD API 2500 Bus Compressor

Given the number of SSL emulations on the market (as reflected in this round-up!), you’d be forgiven for forgetting that bus compressors by other manufacturers are also available – and without doubt one of the finest is UAD’s software remake of API’s classic module, which can be had in both DSP-powered UAD-2 format and as a native UAD Spark plugin. API 2500 Bus Compressor is an absolute triumph, serving up all the features and functions of the hardware, plus Headroom and Mix controls.

Central to the workflow and sound is the Tone section, wherein the Thrust setting filters the detector to balance the frequency response for added punch, the Tone switch flips between feed forward (‘Old’) and feed back (‘New’) behaviours, and three Knee options (‘Hard’, “Medium’ and ‘Soft’) are on offer. Beyond that, variable left/right linking facilitates a high degree of stereo control, and with the Ratio ranging all the way up to inf:1, you can even use API 2500 Bus Compressor as a limiter should you feel the urge. It’s a truly incredible compressor with endless scope for tweaking, and, like The Glue, there’s no reason it couldn’t also be brought to bear on individual channels as well as the 2-bus.

See and hear API 2500 Bus Compressor in action in Brent March’s video.

IK Multimedia Precision Comp/Limiter

The strangely mundane naming of IK’s T-RackS-hosted bus compressor gives no clues as to its origins, but Precision Comp/Limiter is in fact an emulation of the legendary Neve 33609 – a bona fide studio staple since the 1970s, and still very much available in rackmount form. The 33609 is known for its transparency and the supremely gentle nature of its dynamics shaping, and Precision Comp/Limiter replicates those traits to a tee by modelling the full signal path of its separate Compressor and Limiter circuits from start to finish. This two-stage approach sets IK’s entrant apart from the others here and makes it particularly versatile, and the addition of an Input level control only bolsters to that flexibility, enabling overdriving of the signal into the processors for more creative application.

Putting smoothness and musicality at the top of the agenda, and one of very few 33609 emulations available in the software domain, Precision Comp/Limiter is a must-try for fans of that classic British console sound.

SSL Native Bus Compressor 2

Finally, we’re back on the SSL bus, and what should – in theory – be the last word in the emulation thereof. Clearly the most ‘official’ virtual version of the 4000 G Series Bus Compressor that money can buy, SSL’s own rendition comes as close as we can imagine anyone ever coming to capturing the sound and response of its corporeal counterpart. Not only that, but it also works in sidechain filtering and a dry/wet Mix control, a number of new Attack and Release time options, and several extra Ratios including 20:1 and the even more extreme ‘X’ (“greater than 20, but less than infinity”). Once again, all these fancy additions bless Native Bus Compressor 2 with the ability to work its magic effectively on individual mix elements as well as busses, but busses are nonetheless where it feels most at home. Stunning.

Did your top pick of bus compressors make our list? If not, set us straight in the comments.