Allen & Heath MixWizard WZ4 14:4:2

The latest version of the established MixWizard range has more pro features and routing options than you can shake a magic wand at.

I'm always nervous of any piece of audio gear that says 'Professional' on the box as in many cases that's an indication that it isn't — but Allen & Heath make some seriously good kit, so I'll let them off just this once! My first ever grown-up mixer was an Allen & Heath System Eight, and I've had a soft spot for them ever since. Their MixWizard range has been around for a long time now, and this, the fourth incarnation, has such desirable mechanical features as individual circuit cards for the channel strips (rather than having everything on one big circuit board), pots fixed to the front panel with nuts rather than just poking though to the panel, and jack sockets with metal nuts as opposed to plastic ones.

Physically, the console is fairly slim, but the I/O pod lifts the back of the console off whatever it's resting on, to allow a comfortable working angle. Because of its channel count, this particular model can optionally be rackmounted, where the side trims can be removed to allow rack fixing. In desktop 'mode' the console measures 507 x 530 x 194 mm, whereas in rack 'mode' it occupies 10U of space and fits into a standard 19-inch rack. Though by no means unique, another practical feature is that the rear connector pod can be rotated from its default desktop mode to present downward-facing connectors when fitted to a rack. A switching-mode internal power supply enables the console to run from 100-240V, 50/60Hz. Though the control density is fairly high, to make everything fit, the control surface doesn't feel cramped, and the sensible use of colour helps differentiate the control functions.

For live work, the console includes an innovative feature that Allen & Heath have employed on previous models: the console may be configured to work either as a conventional live/studio mixer, or be switched to work as a stage monitor mixer, where the group faders and aux out level controls are swapped so that the six aux-mix outputs are under fader control. This feature is applied on a per-group/aux basis (engaged via a recessed switch above each group/aux fader), and as well as providing a means of controlling the aux masters via faders, it also swaps the outputs of the auxes and groups, so that the aux output is presented on what is normally the group-output XLR, and it has access to the group XLR's insert point (for inserting a graphic EQ across an aux mix, for example). You also have the option of fitting an audio interface card, which makes live multitrack recording possible via USB.

Merlins & Outs

The mixer has a four-band sweepable EQ on all 10 of its mono mic/line input channels, and four mix groups in addition to the main stereo output — plus there's a mono output with its own level control. In normal FOH applications, the mono output might be used to drive a mono fill speaker, to supply a separate zone or even to function as the main output if the sound system is mono. However, another recessed switch on the control surface enables the mono output to be used to drive the mix engineer's wedge monitor, with any AFL/PFL'd signals also being sent there so that the monitor engineer can isolate individual sources. Direct channel outputs provide the option for both live and studio recording applications.

In addition to the 10 mono mic/line inputs, there are two stereo line channels with four-band, non-sweepable EQ. It should also be noted that there are actually two sets of stereo inputs associated with each of the two stereo channels. ST1 and ST2 feed channels 11/12, while ST3 and ST4 feed channels 13/14. Though all their inputs are on TRS jacks, ST1 and ST3 are unbalanced, and each of these two comes in via a simple level control, followed by a routing button that either mixes it in with the stereo channel below it, to allow it to take advantage of the channel EQ and sends (ST2 and ST4), or routes it directly to the main left/right mix bus. As the mixer has no dedicated effects returns, these extra stereo inputs meet that need quite effectively.

The usual two-track input and output phonos are present and, unusually on a console of this size, there's also a two-by-six matrix that can be pressed into service when recording, setting up separate broadcast feeds, sending mixes to multiple zones such as theatre dressing rooms, feeding delay stacks, and so on. This is achieved by means of two matrix mixing strips in the master section, each of which has level controls for the four bus and main L/R sources, as well as a master level control.

The rear panel houses all of the audio input and output sockets, and can be rotated so that the connectors point downwards, for when rackmounting the desk.Other practical features include a test oscillator, a pink-noise generator, comprehensive talkback, LED metering at key points and a four-pin lamp socket. Some of the more sophisticated options require the bottom cover to be removed, and these include allowing aux sends and direct outputs to be sourced pre- or post-EQ, and for the talkback mic input to be phantom-powered or not. The channel direct outputs can also be reconfigured to post-fader, but the default setting is pre-fader, which is probably the most useful (especially for recording). Most of these changes are effected by moving jumpers on the circuit boards, though some mods require a little soldering (the manual provides full details).

The aux and matrix outputs are impedance balanced, which is just as effective as conventional full balancing in suppressing interference, but there is an option to add the necessary components to convert these outputs to full electronic balancing where necessary. Another option is the multitrack USB 2 interface card kit (professional installation recommended), which supports multitrack 24-bit recording of up to 16 channels directly into a computer, with two-track playback, at sample rates of up to 96kHz.

A Kind Of Magic

On the mono mic/line channels, the balanced line-input TRS jack overrides the XLR input once a jack plug is inserted, though the XLR input may also be used for line-level sources. TRS insert jacks (pre-EQ) and direct outs are available on the 10 mic/line channels and the main/bus outs, but not on the stereo channels. At the mic/line inputs the expected pad (20dB) and low-cut (80Hz, second order) switches are present, and the phantom power is also switchable on a per-channel basis rather than being global. All channels include an EQ bypass button, something often missed out on smaller consoles. On the mic/line channels, the EQ has shelving high and low controls augmented by a pair of variable frequency, fixed-Q mid controls, where the lower-mid's range extends from a remarkably low 35Hz to 1kHz, and the upper-mid from 500Hz to 15kHz. For the line channels the mids are set at 250Hz and 2.5kHz. In all cases the high and low shelving sections operate at 12kHz and 80Hz.

Precious Auxes

To exploit the maximum flexibility from the six aux sends, these are split into a group of two and a group of four, where each group can be switched globally to operate pre- or post-fader. These feed master level controls in the master section, with AFL buttons and recessed fader reverse switches. It is important to note that the groups always feed into the matrix and the subgroup pan and routing controls in either mode. Below the EQ is the long-throw channel fader and pan control, along with mute, PFL and routing buttons, and a pair of green and red LEDs act as signal-present and overload indicators.

The recessed blue switches above the faders 'flip' them so that they can control either the aux outs or the group outs.Given the flexibility of this desk, the master section is surprisingly straightforward. There are faders for the groups and for the two main outputs (separate left and right faders, and each of the four groups has a switch enabling it to be routed to the main outputs, with a pan control steering it between the left and right outputs. Four-stage LED level meters are provided for each of the four groups and for the main outputs, as well as mute and AFL buttons. The two main console meters are 12-LED affairs, and also serve to show AFL or PFL levels. An XLR with a gain trim control is located at the top right of the panel for connecting a talkback mic, which may be routed to any combination of the buses and main outputs, and is activated using a non-latching master switch. In the same section is the headphones output jack (which can monitor the L/R output or two-track return), a level control and L/R routing button for the two-track analogue or USB (if fitted) return, a switch to select oscillator or pink noise, and a level control and recessed On button for activating the selected test signal. Separate monitor outputs are also available, controlled via a dedicated monitor level control, while the mono out also has its own level knob.

A standard USB 2 port accesses the optional USB 2 expansion card, where a recessed switch selects the two-track input source as either the phono returns or the USB port. The USB feeds are sourced from the mono channel direct outs, the insert sends on the four groups, and then either the main left/right output insert sends or the two matrix outputs. A recessed switch to the left of the USB socket selects the last option. In addition to using the two-channel return for playback, it should also be practical to use it as an effects return path should you wish to use computer-hosted effects in the mix.

Spellbinding

Technically the mixer performs well, with low-noise mic amps (EIN -127dB) and plenty of headroom, with the ability to supply up to 26dBu at all the main XLR outputs and 21dBu at the jack outputs. The frequency response is sensibly flat (20Hz to 50kHz within ±0.5dB) and I didn't notice any crosstalk during normal operation.

Allen & Heath have their own Mac and Windows USB drivers downloadable from their web site, and although the Apple driver is only listed as supporting up to Mac Mountain Lion, it worked fine on my Macbook Pro laptop running the current version of Mavericks (10.9.2), albeit with a warning message that I was using an unrecognised Kernel Extension. With a buffer size of 128 and running at 44.1kHz, Logic X reported a round-trip latency of a hair under 12ms and a playback-to-output latency of around 7.5ms. I experienced no distortion or glitching problems.

Conceptually the mixer is well thought-out, easy to navigate and designed to be reasonably straightforward to service thanks to those separate channel circuit boards. I also like the way the connector pod can be repositioned for rackmounting. My own preference is for mixers with built-in delay and reverb effects, as that makes setting up so much easier than carting extra boxes and cables to gigs, but if you are happy to patch in your own, then this mixer should meet your needs. For live-sound applications the dedicated stereo line inputs are less useful than the mic ones, other than as effects returns, as any live sources fed from the stage tend to go to the multicore via DI boxes, and terminate at a console mic input. However, they do come into their own in a studio setting, for handling MIDI instruments, modelling guitar preamps and so on. That said, the sister products in the MixWizard range, such as the 12:2 and 16:2, offer built-in, high-quality effects and the 16:2 has 16 mono input channels, each with XLR inputs, for easy multicore connection — although that model forgoes the group and matrix facilities.

There are many 'behind the scenes' plus points to this desk, such as the inclusion of jumpers to allow the user to reconfigure aspects of the signal flow, and the ability to switch the mixer to monitor mode. As reported, some of the less common routing options require a little soldering, but it's better to have them than not. I also like the very conventional layout, which means pretty much any engineer should feel right at home behind the console, even without looking at the manual. Also worthy of mention is the wide EQ range, especially the lower-mid that can reach right down to the bass if required. Too often, console EQs lack the low-end reach to address lower-mid boxiness, but there are no such limitations here. What's more, Allen & Heath EQ sections always sound classy and clean, this one being no exception. Adding the USB card makes comprehensive live recording possible with the minimum of fuss, and is a great way to make a little extra cash when hiring yourself out for PA jobs, so I think it is well worth having.

Although I might choose one of the 'with effects' models for my own live-sound applications, with the WZ4 14:4:2 Allen & Heath have produced a solid, great-sounding, well-engineered mixer that has a lot of flexibility built in.