Focusrite Liquid Mix

If you're looking for characterful compression and EQ to warm up your computer-based mixes, Focusrite's Liquid Mix might just be the answer.

Focusrite's Liquid Mix is a DSP-powered add-on for your computer that hosts a large range of compressor and equaliser plug-ins, all created using a novel form of convolution technology to measure and then emulate the audio characteristics of hardware devices. We carried a fairly detailed preview a couple of months ago, but now that the production version (v1.2) is shipping, we've had a chance to put all its emulated EQs and compressors to the test and also to try out some small updates to the original software.

For the benefit of those who may have missed our preview, the Liquid Mix is based on the DSP-powered compressor and EQ sections of Focusrite's Liquid Channel, and packages these processes into plug-ins that can be used in a Mac or PC-based recording system. Up to 32 channels of EQ and compression can be used at the same time via the insert points and busses of your chosen DAW software, and because the plug-ins run on the Liquid Mix's DSP rather than the host CPU, there's very little extra load on the computer, even when the maximum 32 channels of processing are running.

Unlike competing DSP plug-in platforms, the Liquid Mix hardware also includes a desktop control surface for the plug-ins. It connects to the computer via Firewire, and in most cases can be buss-powered, though a power adaptor is included for those occasions where buss power isn't available. The desktop unit has physical knobs and buttons to control the plug-ins, hardware metering for level and gain reduction, and a small display window that shows the current EQ or compressor curves as well as other parameter information.

Mix And Match

Each instance of the Liquid Mix plug-in can run a range of EQ and dynamics processing modules (one of each per instance of the plug-in) that emulate various pieces of current or vintage studio EQ and compressor hardware. As with the SSL Duende, the Mac version is now shipping, and the PC/Windows version will follow on a little later. The Liquid Mix supports VST and Audio Units natively, and can be used with Pro Tools via an adaptor. At launch, the user has a choice of 20 EQs and 40 compressor types, and Focusrite tell us that further new emulations may be made available from their web site; there is already the ability to create hybrid equalisers of your own design by combining different EQ bands from different emulations. The maximum channel count of 32 plug-ins is available at 44.1 and 48 kHz sampling rates; it drops to eight at 88.2 and 96 kHz, and just two plug-ins at 192kHz. An optional expander card doubles the DSP power to double the track count at higher sample rates but you're still limited to a maximum of 32 simultaneous plug-ins at 44.1 and 48 kHz.

As a controller, the Liquid Mix provides continuous rotary knobs for the input Level, compressor Threshold, Ratio, Attack, Release and Gain Makeup, plus Gain, Frequency and Q controls for a single EQ band. A further turn-and-push knob moves between EQ bands; the currently selected band is shown on the hardware LCD, and identified on your computer's screen by having a pink centre to the knob. The controller allows you to select which Liquid Mix plug-in is being controlled, so it doesn't necessarily have to be the one in the currently selected DAW track. Hardware buttons are available for saving and loading presets where the host DAW supports it, and there are bypass buttons for the compressor and EQ sections and individual EQ bands, as well as for the whole plug-in.

As well as the LCD, visual feedback on the Liquid Mix hardware also includes a master EQ output level control and metering for the input, the compressor gain reduction and the output. A further meter shows the level between the EQ and compressor, just to make sure you're not overloading anything there by adding too much gain. Graphs show the compressor curve and the EQ function: the composite EQ curve is displayed in blue, with the contribution of the band currently being adjusted shown in red. When the plug-in loads, all the EQ bands are bypassed and so must be enabled as required; shift-clicking on the EQ button enables or disables them all at once. The same seven-band EQ layout is used for all the equalisers; any knobs that are unused in a particular EQ emulation are greyed out, unless you decide to build a hybrid 'mixed' EQ by adding bands from another model.

Many of the equalisers offer cut and boost, but some of the passive-style equalisers emulated only allow you to cut, meaning that the flat position is fully clockwise. Some of the classic EQ emulations also have the normal HF-at-the-right control order reversed, and on some, the frequency control decreases the frequency as you move it clockwise, presumably because that's how the original was set out. I'm in two minds as to whether this is taking authenticity too far, as the panel layout doesn't try to emulate the hardware being mimicked in any other obvious way, and there's a lot to be said for consistent control layout and behaviour.

The EQ and compressor emulations are selected from drop-down menus and there's the usual ability to save and load plug-in settings directly into the DAW, plus buttons within the plug-in for saving and loading snapshots — which seem to be the same thing. What I couldn't find a way to do was save and load individual settings for the compressor and EQ sections: both are always saved together. All the plug-in parameters can be automated when controlled from the screen, and in the case of Logic at least, automation is also recorded correctly when you use the physical controls.

Along the lower left edge of the plug-in window are buttons for reversing the positions of the compressor and EQ and for accessing the side-chain monitoring, though despite claims that side-chaining is possible on models that originally featured side-chain inputs, I could find no obvious facility for feeding a separate audio track into the side-chain for ducking or similar operations. I checked this with Focusrite and they told me they'd removed this from the first release so they could get a stable version to market, but they plan to reintroduce it in version 2 of the software.

The same set of buttons are doubled up on the hardware and the plug-in window other than the separate band enable buttons, which are only on the plug-in. On the hardware there's just one button to bypass the currently selected EQ band and another to bypass the entire EQ section. Stereo linking has its own button, while Free allows the parameter values to be made fully variable in cases where the original hardware being emulated was fitted with stepped switches rather than knobs.

In Use

I tested the Liquid Mix with Apple Logic Pro 7.2, where the Liquid Mix plug-ins appear just like any others. The Liquid Mix Manager panel allows you to change the maximum number of plug-ins you wish to run, and this has an effect on the amount of Firewire bandwidth the unit reserves. Regardless of which compressors and EQs you wish to use, you simply load in the Liquid Mix plug-in (mono or stereo) and then select the desired compressor and/or EQ from within the plug-in window. Once loaded you need to switch on any EQ bands you wish to use before you can hear the results of any adjustments.

The unit seems very happy powered from a six-pin Firewire socket on the computer, but it may be worth adding a PCI Firewire card if you have a lot of other Firewire peripherals so as not to eat up too much bandwidth on the Firewire buss. When I wrote the preview of the Liquid Mix using a beta version of the software and firmware, it wouldn't work in the same system as my Belkin Firewire hub, but that conflict now seems to have been resolved. Earlier versions also struggled when some other Firewire DSP devices were connected, but again, the latest software revision seems to have fixed this. The current release software version requires Mac OS 10.3.9 or later, and Focusrite have already managed to include Universal Binary support for the new Intel Macs.

The names of the different compressor and EQ patches only provide clues as to what they emulate, but see the 'Behind The Mask' box for a list of the real-life models that were researched in their creation. These range from expensive and rare outboard to popular consoles and workhorse rack gear, and the selection on offer is certainly impressive, covering many of the biggest and best-respected names in recording hardware from both the UK and the US, including a number of Focusrite's own products.

Too Much Choice?

Having such an impressive list of compressors and EQs to choose from can be a little overwhelming, especially if you're struggling with the basics of EQ and compression in the first place, but it makes you appreciate how different some of them sound. You don't get a lookalike plug-in interface for each device emulated — all have the same interface, which on the plus side, means that you judge them all by their sound and not by their cosmetics. Having physical knobs to adjust the plug-ins, not to mention hardware meters, is very welcome.

To set up a mixed EQ hybrid, you simply click on any of the knobs in the desired EQ band to select it, then go to the EQ menu and follow the arrowhead that leads to a submenu of 'root' EQ bands that can be loaded into the currently selected band. You can do the same thing from the hardware controller by pressing the Emulation Select button, which brings up a list of EQ types on screen. You can scroll through these using the data knob, after which pressing Emulation Select again brings up the EQ band menu allowing you to choose one. The process can be cancelled at any stage using the Go Back button. To select an empty band from the hardware, you need to press and turn the data encoder to navigate to the empty band, after which you can load your desired EQ section into it. I once managed to set up a hybrid EQ that seemed to distort rather badly when I applied a lot of upper mid-boost, even though the meters were happy, but for the most part the system works perfectly, and I never managed to recreate the problem after that.

The Liquid Mix Manager software allows you to set the unit's sample rate, and also to specify the maximum number of channels of processing you wish to use, in case you want to conserve Firewire bandwidth.Operating the Liquid Mix is gratifyingly straightforward, and though some users might wish for photorealistic emulations of every plug-in control surface, there's a lot to be said for having a consistent control style. This being said, I personally find it less helpful when the normal layout is changed to reflect some of the oddities of the original, such as putting the HF controls on the left or having frequency controls that work backwards. While I'm making small gripes, I couldn't get the Snapshot facility to work in Logic, though the normal Save and Load menu does essentially the same thing, and does work. The compressor and EQ settings are always loaded together, though, and I feel it would make more sense to also have them available separately.

Sonically, I'm not able to vouch for the degree of authenticity of all the emulations, but there are some very nice-sounding EQs and compressors available covering a wide range of distinctive characters and styles. I particularly liked some of the more subtle passive EQs that seem to sweeten a mix or track with very little adjustment, and of course there are those kick-ass optical compressors that contrast nicely with the more workmanlike VCA versions. For the less experienced user, deciding which to use may present a challenge, but at the same time Liquid Mix offers a wonderful educational opportunity for any aspiring engineer to get familiar with the essential character of a number of classic compressors and equalisers that they may otherwise never come across.

The emulations used in the Liquid Mix come directly from the high-end Focusrite Liquid Channel, and as such, sound extremely smooth and — dare I say it — analogue. Though not exhaustive, they cover all the major styles of compressor and EQ, and the ability to control them from a sensibly small desktop unit with physical knobs on is supremely attractive. The facility to cook up your own hybrid equalisers by combining bands from different models is also intriguing, though there are few jobs that couldn't be tackled with the emulations already available. The user interface has already seen some improvements since version 1.0, and I'm sure Focusrite will continue to develop it.

By way of value, what the Liquid Mix offers is outstanding, with up to 32 simultaneous channels available. Focusrite could probably have charged twice as much and nobody would have batted an eyelid. It's also worth remembering that compressors and equalisers are the most used processors in any normal mix situation, so being able to choose from so many high-quality options without placing any real load on your computer's CPU is a significant practical benefit. The Liquid Mix offers some genuinely useful alternatives to the compressors and equalisers that come with typical DAW packages. And if you want a more superficial reason to buy one, it looks really cool sitting on your desk!