Focusrite Liquid Mix

Using hardware DSP to assist your computer isn’t new, going back to at least Digidesign’s Sound Accelerator card. Creamware, E-mu, TC Electronic, Universal Audio, Waves, and others have all come up with hardware solutions designed to do one thing: provide massive amounts of DSP power that doesn’t load down your CPU.
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Unlike native processing, hardware-based DSP also offers a fixed amount of power. With a computer, the amount of CPU drain fluctuates based on several factors, so you always need to leave some breathing room. But you can pretty much “red-line” DSP without worries.

Focusrite’s Liquid Mix is an external FireWire 400 device (currently Mac PPC/Intel/OSX compatible, but a Windows version is slated soon) charged with one task: deliver an array of vintage EQ and compressor effects. So is it indeed cool? Let’s find out.


I hooked up a FireWire cable to the cute hardware box, and installed the software. And of course, I went to the website to check for an update and of course, there was one — so I installed that too.

And a guest is no good without a host, so Digital Performer 5 took care of that (which also has some tasty EQs of its own, which I figured would be good for comparison).

I opened an electro-type piece I’d been working on, went to an insert, selected Liquid Mix, and a warning appeared that it couldn’t work because the buffer size was larger than 1,024 samples. But I checked in DP, and the buffer size was 256 samples. Huh? Then I realized I was too eager to try the thing out, and hadn’t rebooted after installation. Oops. Once I did, everything worked flawlessly.


You can have 32 mono “channels” (or 16 stereo), with both EQ and compression, at 44.1/48kHz. Raising the sample rate decreases the available number of channels, but an expansion card (not included with the review unit) helps compensate for this. For example, at 88.2/96kHz you can run eight mono channels or four stereo channels and at 176.4/192kHz, two mono or one stereo channel; adding the expansion card doubles those figures.

Also note that you can’t expand the number of channels by daisy-chaining units. Of course I wanted to see if I could max it out, and indeed, after 16 stereo channels at 44.1kHz, it politely informed me that was it.

Is this a problem? I don’t think so. The convolution-based models of the various compressors and EQs have “character,” and I think you would tend to apply them to change not only EQ and dynamics, but impart a bit of personality to a sound. If all you need is a simple bass or treble shelf, your host EQ can handle that. And if it can’t, premix the track using the Liquid Mix to free up resources.


One of several outstanding Liquid Mix features is that Focusrite has grafted a nifty control surface onto their FireWire box. It’s compact but not cramped, and has a very high-end vibe thanks to sculpted knobs, a striking blue display, four 12-step LED meters, buttons that illuminate green when pressed, and 11 knobs.

Although you can adjust the parameters on-screen, it’s well worth putting the control surface in a prominent place on your desk, and using that instead. As not all models utilize all controls, an LED on the control surface indicates which controls are present, and settings are confirmed in the LCD (which also indicates which parameters are and are not available). About the only awkward aspect is that selecting a strip on-screen does not call up the equivalent strip in the controller: You have to select the strip you want to work with manually. However, if you have lots of instances running, I actually found it easier to use the controller.

One final controller advantage is that a couple dozen plug-ins take up a fair amount of space on-screen. So you can minimize them with impunity, then run them off the controller. Bottom line: The hardware is a definite workflow enhancer.


There are 20 EQ and 40 compressor models, spanning a variety of “vintage” and modern devices. (Focusrite says there will also be free, additional models available online in the future.)

The model descriptions are not too helpful — you’ll see names like “Huge Tube: US Modern Tube 6 EQ” and “Brit Desk 5: Brit Modern Desk 3 EQ.” (At least I figured out that the number in the second part of the EQ description was the number of active bands.) This means you have some auditioning ahead to figure out what each of the models actually does.

It’s a bit easier to figure out the compressors because as soon as you call one up, you see a transfer curve in the compressor graph. For example, “US: Vintage Tube 1” has a steep knee that gets pretty flat pretty fast, and omits ratio and attack controls — it’s pretty obvious this is your “fun with squashing” compressor. On the other hand, the “London: Brit Boutique Tube 1” has a gentle, sloping knee; if you bring up the threshold to a reasonable value, this does a fantastic job of bringing up a sound in the mix, but without any obvious dynamics effect.

If you instead want a track to scream, “I’m being compressed,” the “Big Green: Brit Classic Optical” model has a transfer curve that flattens out, but then starts climbing again. The result is that there’s a lot of squashing going on, but the peaks get a little extra lift.

Also cool: a “free” button for the compression, which with vintage models, makes the full set of controls available even if a particular control was not available with the original emulation. You’ll also find a link control in stereo mode (so it operates as a stereo compressor or dual mono). The enigmatic sidechain monitor button seems out of place; you can’t actually feed a sidechain signal into the compressor, so it ends up monitoring what’s at the input. Then again, there are rumors floating around that future plug-in specs will include true sidechain options and if so, this is going to look like a pretty prescient button someday. Finally, you can place the compressor pre- or post-EQ (thank you!).

I found it a little bit harder to differentiate among the EQs, because their complement of controls follow the emulations reasonably closely. This made it hard to do direct comparisons, as one might have a stepped midrange control that covered only certain frequencies not covered by other types of EQ. Still, the differences in “character” were obvious. For example, some midrange peaks had a “meatier” sound, while others were more subtle.

But there’s more: You can load individual bands from different EQs into each of the available seven bands, so you could have the low shelving band from one EQ, a midrange boost from another, and so on. Amazing.

Difficult to manage, right? Not really; when you find favorite settings, you can save these as snapshots for later recall. This of course is in addition to the fact that settings are saved within your host program.


I was skeptical when I started this review. Sure, Focusrite makes great stuff, and Liquid Mix looked promising. But the world of compressor and EQ plug-ins is not exactly under-populated, and there are fine external DSP solutions. Besides, for $1,100 you can buy a lot of native plug-ins.

Then things started falling into place. First, it installed easily and was obvious to figure out. Second, despite piling on the Liquid Mix plug-ins in Performer, the CPU meter kept reminding me that none of this was affecting the CPU much. And while Focusrite is upfront about the FireWire aspect, adding about 2–3 ms of latency, I didn’t notice any significant lag while adjusting the controls.

As I got deeper into using it, two things stood out: The sound quality is just plain wonderful, and so is the interface. It didn’t take long to become familiar with the control surface, and yes, it does speed things up.

My only real concern is that it takes a while to really learn the “sound” of the various models. Until you do, it’s a temptation to try everything on a track to hear what works best. That can be a time sink, so my advice is simple: When you find a sound you like, stop there. Sure, maybe you could find something even better, but the object is to create recordings, not tweak forever. I’ve always maintained that just because a piece of gear has a particular feature doesn’t mean you have to use it, but Liquid Mix really puts one’s self-restraint to the test.

It’s also worth noting that although there are some “plain” models, there are also plenty of models that add real character to the sound, almost like a signal processor. That’s one of the factors that makes Liquid Mix cool: Those various models really do give you an arsenal of sounds that would formerly have taken a truckload of rack mount gear.

Given that one of the weak links in host software is often EQ (because you sometimes need a lot of instances, but they can’t take up so many CPU cycles that you end up killing your processor’s performance), Liquid Mix gives you great EQ and compression while leaving your CPU free to run CPU-hungry instruments and processors like convolution reverb. I don’t know if I’d consider this an essential purchase for those with seriously constrained budgets, but if you can spare the bucks, Liquid Mix will definitely help take the sound of your native-based DAW setup to the next level. Maybe even the level after that, too.

Product type: DSP processor for software-based hosts.

Target market: Native-based studios wanting higher-quality compression and EQ without loading down the host computer.

Strengths: Includes great control surface. Plenty of models, with lots of character and variations. Easy to understand and use. Sounds really good. Does VST/AU (and RTAS via a wrapper). Adds only a couple milliseconds to system latency. Includes power supply for use with four-pin FireWire ports.

Limitations: Selecting a plug-in in your host doesn’t change it in the controller. Not expandable for more channels at 44.1/48kHz.

Price: $1,099.99