Brief Summary

Although plugins do the job brilliantly, a hardware bus compressor might be a way to introduce consistency and personality into your mixing. And there are a lot to choose from beyond the big names.

Going Deeper

Along with a mic preamp the next piece of hardware you’re most likely to find in a typical DAW based studio is a compressor. Many people might be looking for a channel compressor to commit a sound on the way in but just as many people will be looking for something to give some analogue goodness to the stereo bus. In this article we look at some contenders in an area of the market which has options from venerated classics to options for the budget conscious.

What Are You Looking For?

When we talk about bus compression, do you know what you want? Depending on the specifics of your work you do and the style of compression you prefer it’s very likely that there is something out there which will fit the bill, the question is, in an age of excellent plugins, why would you?

Plugins can be part of the answer here as is it so easy to download and audition plugin versions of hardware that familiarising yourself with what works for you can all be done in software. But it doesn’t have to stay in software.

I’ve Got Plugins For That

I’m not going to say that plugins are indistinguishable from the real thing, but I will say that plugins are so good that it makes no practical difference. However some quality hardware across the mix bus does bring things that using plugins does not. And if I’m only going to have one processor across the mix bus it’s going to be a compressor. What is the advantage of using hardware?

It brings focus. I have my regular go-to bus compressor plugins. Which one I’ll use depends on what I’m doing but most of the time it’s an SSL style bus compressor. I often experiment with an alternative. Like most of us I have too many plugins and feel the need to at least try something else. Having a single hardware bus compressor makes me concentrate on the compression rather than the compressor. The two are related but not the same.

One of the principal reasons why most people avoid using hardware during mixing is the necessity of recall. For an entire mix this is too inflexible for all but the most dogmatic of hardware enthusiasts, but on the 2 bus recall is little more than a handful of controls. For those who want to make sure that information stays with the mix there is the ingenious Snapshot 2 plugin from Non-lethal Applications which allows you to store photographs of hardware in your session.

When it comes to the sound, while you can argue that your plugin sounds as good as the hardware, the hardware is still the hardware. But the other reason hardware is so attractive in use is the physicality of it, the ‘handshake’ for want of a better word. And however good the graphics are in a plugin there is no substitute for the ballistics of a real moving coil VU meter, a fact recognised by SSL in their UC1 Plugin Controller which features a real VU meter controlled by the plugin.

On the subject of SSL, when discussing bus compressors the legacy of the SSL bus compressor looms large, as discussed in our article Is Classic Studio Gear Really That Good? Maybe it was the fact that that particular bus compressor was built into the consoles on which the most important records of an entire era were mixed which meant that it shaped our expectation of what a record should sound like, but the VCA based SSL bus compressor is mandatory on any list, whether hardware or software. Passing over the Townhouse bus compressor, built from SSL parts for Townhouse’s Non SSL studio, it was some years before you could buy a standalone compressor from SSL. Alan Smart’s C1 and C2 versions were early third party options but now there are SSL bus compressors from DIY kits to the real deal and it is the latter we’ll in include in this list.

The Mandatory SSL Compressor

SSL THE BUS + $2899

The newest incarnation of the SSL bus compressor from SSL is THE BUS +. A lot of the appeal of the original SSL Bus Comp is its simplicity. A handful of controls mean it gets dialled in quickly. SSL have seriously updated the feature set with this 2U rackmount unit, including a low THD mode which cleans up the bottom end, a Feedback mode for more relaxed compression and a 4K mode which changes the character from the clean sound of the 9000 series to the grittier sound associated with those early consoles.

The upshot of this is that if you are familiar with an SSL compressor you can use it precisely like that but the additional features mean that there is room to grow into your mix bus as you get to know it. We think it’s got enough flexibility to fit any project but won’t overwhelm you with options when you’re dialling in a sound.

A Different Take On An SSL

Tierra Audio Gravity $1632

The simplicity of the SSL is a beautiful thing, and something which has made it a longstanding preference for me. I used to feel like I was being lazy or fraudulent when I hardly ever changed my settings when using the SSL XR626 X-Rack version of the classic G Series compressor. It was in conversation with a former house engineer from a historic London studio that he told me that they had a setting which got used on nearly everything. It was the same as mine! 2:1, attack on .3, release on auto.

This simplicity is beautifully repackaged in the Tierra Audio, a compressor we’re looking forward to trying as, as well as being a VCA design which is true to the ethos and sound of the original SSL, it is also a responsible purchase. If like me you are tired of unmaintainable equipment which can’t be fixed by a capable tech with a schematic and a soldering Iron it’s good to see some handmade equipment with through hole soldering, wooden front panels and all-recycled cardboard packaging. They even plant a tree for every unit sold!

For A Vintage Neve Experience

Heritage Audio 609a $1999

Most of us are familiar with VCA, FET, Optical and Vari-Mu, the four main designs of analogue compressor. There is a classic design which achieved its results using a different method - The diode bridge designs pioneered by Neve. The 33609 is a classic and once you tune into its character you’ll find it both characterful and flexible. The Neve hardware is of course available but when I tried the Heritage Audio HA 609a I found all the appealing character of the Neve units I’ve been lucky enough to use but in a far more affordable package. The RAF blue metalwork and Marconi knobs add to the experience and I have to say I was sorry to see it go. I’d been an SSL user until spending time with this one but my expectations around its flexibility were proved wrong. If you can’t get a Neve style compressor to sound good on your mix its probably not the compressor’s fault.

For Straight Ahead, All In One Processing

Tegler Audio Creme $1906

If I were buying a single unit for my 2 bus it would be a compressor, however it might not only be a compressor. It’s a safe bet that a bit of broad brush sweetening EQ is going to find its way onto most stereo busses, just ask Pultec and Manley. The Tegler Audio Creme combines a flexible VCA stereo compressor section with a passive, boost-only EQ for lifting the highs and filling out those lows. The order of the compressor and EQ can be reversed and with a high pass filter on the  compressor detector you can make sure that your bottom end doesn’t dominate the compression.

If you want a polished sound from a single hardware unit, the Creme will get you there without any fuss or faff.

Something Different

Daking Comp II $1599

Audio types are a pretty conservative bunch. We sometimes over-focus on a surprisingly small number of candidates in any category of gear. For example the majority of hardware compressors are VCA designs, but a handful of VCA compressors dominate our perception of the category. Think of a VCA compressor and you’re probably thinking of an SSL or a DBX. Our last entry is the Daking Comp II, a simple high quality VCA compressor which satisfied the discerning ears of William Wittman, a man who has a long standing preference for the FET based Audio and Design Compex compressor. Check out his thoughts and hear the results in his article Think You Don't Need Another Hardware Compressor?

I Don’t Need A Bus Compressor

You might think you don’t need and bus compressor. You’re absolutely right, no-one needs a bus compressor. Plugins are great. However you might find your mixes improve if you get one. And there’s never been a better time to check out the options. These might seem expensive compared to a plugin. But to compare them to a plugin would be missing something. I have hardware I’ve owned for thirty years. I can’t say the same of plugins or the computers which ran them!

What would you like to have seen on this list?

A Word About This Article

As the Experts team considered how we could better help the community we thought that some of you are time poor and don’t have the time to read a long article or a watch a long video. In 2023 we are going to be trying out articles that have the fast takeaway right at the start and then an opportunity to go deeper if you wish. Let us know if you like this idea in the comment