Allen & Heath ZED R16

If you want to use both a high-quality analogue mixer and a DAW control surface, you'll probably want to put them both in the same place. Well, now you can - and you get a multi-channel audio interface to boot.

Photo: Mike CameronAllen & Heath's ZED R16 is their first new recording-oriented console for over a decade. Its feature set is tailored primarily to the DAW user, with a multi-channel Firewire audio interface under the hood, and plenty of MIDI control thrown in for good measure. But at a time when people seem to be selling their mixers, why should we want to buy this one?

It's a paradoxical state of affairs, but the more our studios become reliant on digital gear, the more we can't get enough of analogue. And why not? Where digital is precise, controllable and predictable, good analogue equipment is characterful and tactile — and it often has an indefinable funk-factor. Of course, the two can complement each other beautifully: the trick is knowing how — and at what points in your signal chain and production process — to harness the merits of each.

The ZED R16 consciously attempts to marry digital and analogue in a way that's useful to a wide range of users. We'll get into the detail later on, but essentially the design trades a number of features (like group channels) that might be considered standard on a studio or live console for specialised functions that make it fit better in the modern computer-based studio. The emphasis on flexibility should ensure this mixer has a use in everything from single-laptop bedroom setups, through project and small commercial studios, to the location and live fields.

Out Of The Box

So you've coughed up for the ZED R16: what exactly do you get? At around 13kg (29lb) and with maximum dimensions of 70cm x 47cm x 10cm, this is by no means a room-filling mixer, but it's certainly hefty enough to form the centrepiece of an impressive setup. The build quality is outstanding: apart from the red cheek-panels, which are a tough ABS-like plastic, the rest of the case is metal, and there are individually mounted circuit boards for the input channels — a very grown-up feature, which makes servicing easier and promises better long-term reliability. Similarly, every rotary control on the front panel is secured with a metal nut, providing additional protection to the internal circuitry.

As well as your snazzy red and grey mixer, there's an IEC mains lead, and you get both six-pin to six-pin and six-pin to four-pin Firewire cables. PC users can make use of the bundled Sonar LE software, and there's also a printed User Guide.

Drivers for XP, Vista and Mac OS 10.4.11 and 10.5.2 and later will be included, and can be downloaded from www.allen-heath.com/zed. The printed manual and web site are also due to be updated with more specific information about Mac installation and setup with a range of DAWs and ADAT recorders. There's nothing wrong with the early-version manual that came with the review model: it is accurate and useful. But aspects of this mixer could present an almost vertical learning curve to the novice who doesn't have a good grasp of mixer signal-routing and recording workflow, so some additional hand-holding on basic concepts and specific features would be welcome.

Analogue Channels

The ZED R16 has 28 analogue inputs, when the mono and stereo channels and two-track inputs are taken into consideration. Starting with the mono inputs, there are 16 identical channels, each with XLR and quarter-inch balanced line inputs, along with a quarter-inch insert socket. Phantom power is switchable for each channel, which is a nice touch. Gain is variable from +6 to +60dB for XLR inputs and from -14 to +40dB for the line ins. A 100Hz 12dB/octave high-pass filter affects both mic and line inputs and comes before the insert point and EQ in the signal chain.

The mono channels' four-band EQ is quite extensive for a mixer of this size. The HF band has a corner frequency of 12kHz and a smooth shelf-type response curve that reaches down to around 1000Hz. The LF band is also a shelf, with a corner frequency of 60Hz, but with plenty of effect in the musically useful range up to 500Hz and beyond. Both are capable of up to 15dB cut or boost. The remaining two bands — high-mid frequency (HMF) and low-mid frequency (LMF) — are parametric, with knobs for gain, frequency-centre and Q (bandwidth), as you'd expect. Again, cuts and boosts of up to 15dB are available, and both offer Q factors of between 0.8 (nearly two octaves) and 6 (a few semitones). The LMF frequency can be swept from a remarkable 18Hz to 1kHz, and the HMF goes from 400Hz to 18kHz. Usefully, all four bands can be switched in and out on each channel.

Next on the mono channels come four aux sends: sends 1 and 2 are pre-fader, and 3 and 4 post. There's also a pan pot, a channel-mute switch and red indicator LED, and a pre-fade listen button with a yellow LED. A green LED marked 'SIG' indicates the presence of a -14dB signal on the channel, whilst a partnering red LED marked 'HI' lights when the input signal is within 5dB of clipping. The signal level is measured post-EQ and pre-fader.

Right down at the bottom of the mono input channels there's a 60mm fader (which can be used to apply up to +10dB of gain) and a routing button that connects the channel to the main L-R mix bus. There are also four round buttons with attendant LEDs which, at first glance, you might take for the group assigns on a conventional eight-bus desk. Actually, the top three control how the channel interacts with the ZED R16's 'hidden' Firewire (or ADAT) digital sends and returns, and the bottom one causes the fader to transmit MIDI continuous controller values. If you're thinking 'what...?' at this point, hang in there, because we'll get to grips with the digital and MIDI interfacing later on.

Moving on, there are four stereo input channels towards the top right. All offer balanced quarter-inch line inputs, a gain control, a PFL button with LED indicator and an L-R bus routing switch. Additionally, ST1 and ST2 have unbalanced RCA/phono input sockets, two-band EQ (the same high and low shelves as the mono channels), pre-fade sends to the Aux 1 and 2 buses, a left-right balance pot, and a separate level pot.

Two pairs of two-track inputs are offered at the very top right of the panel — one on phono sockets, the other on balanced quarter-inch jacks. The only dedicated controls for these are in what Allen & Heath call the Master section, to the right of the main L-R faders.

Analogue Outputs

Because this mixer has no groups in the traditional sense, there aren't that many outputs — but the ones that are provided have been carefully considered. The main stereo outs are on male XLR sockets, mirrored by a '2-track 2' output on balanced quarter-inch jacks, and a pair of main L-R insert points just before the main L-R faders in the signal path. There's another pair of quarter-inch jacks to feed your control room monitors, and another pair labelled 'ALT' that could be used to hook up a secondary pair of nearfield or 'grotbox' monitors.

Two additional stereo output pairs, again on quarter-inch jacks, are labelled 'Studio 1' and 'Studio 2', the idea being that these feed headphone amps or 'listenback' monitors in the live room. These have identical panel controls: five buttons that allow any combination of the main mix and the four auxes to form the output feed, a level control, and an AFL (after-fader listen) button, with LED, that allows the engineer in the control room to check what's being sent to these outputs. The only other analogue outs are the four quarter-inch balanced Aux masters, each of which has level controls and an AFL button with LED indicators, and a pair of headphone sockets (one presented on a quarter-inch jack, the other a mini-jack).

Digital Connections

The ZED R16 departs from conventional analogue mixer design with the inclusion of extensive A-D and D-A conversion facilities, allowing you to interface with a PC or Mac via Firewire, or with ADAT-equipped gear such as mic preamps and multitrack recorders.

On first appearances, you'd hardly guess this connectivity was there: there are no LCD displays, no function buttons (or, indeed, any configuration buttons of any kind), except for those I previously mentioned at the bottom of each mono channel strip. The giveaway sign is on the rear panel: two six-pin Firewire 400 sockets, four ADAT optical (lightpipe) sockets providing 16 channels in and out, and two flush-mounted switches to set basic operation mode and ADAT sample rate. There's also a single MIDI Out socket.

Computer Magic

This mixer will probably be used most often with a computer-based DAW via Firewire, to provide both an analogue 'front end' and a multi-channel audio interface. So, with its mixing, monitoring and control-room facilities it essentially offers an all-in-one solution.

Where you'd usually find buttons to route the signal to groups, the ZED R16 has buttons to determine the signal flow between the analogue mixer and your DAW, and to assign the faders as MIDI controllers.Photo: Mike CameronAs a Mac user, I couldn't test the ZED R16 with the bundled copy of Sonar LE, but given that it appears to have a limit on the number of input and output channels that can be simultaneously enabled — and that this is less than the number of digital sends and returns available from and to the ZED R16 — the choice of Sonar LE isn't perfect. However, it's better than nothing, and most prospective users will already own more suitable software.

On my G5 Mac running OS 10.5.4 the driver installation was quick and painless. The only outwardly noticeable change was a new System Preferences pane, which allows various aspects of the ZED R16's operation to be configured, including sample rate. A clutch of other obscure options are available — but undocumented, so I didn't touch them! In Windows XP and Vista, the same functionality is provided through the Control Panel, and a shortcut is placed on your desktop.

If you're working in Firewire mode at 44.1 or 48kHz, the ZED R16 appears in your DAW as an audio interface with 26 inputs and outputs (the eight ADAT ins and outs appear in your DAW alongside the mono channels and stereo L-R mix). When you connect via Firewire at 88.2 or 96kHz sample rates, the Main L-R feeds are lost, and the additional ADAT inputs and outputs are disabled. Although mapping all the physical channels to your DAW may look rather complicated, it's actually quite straightforward.

So what can you do with all these inputs, outputs and special features? Let's consider a couple of practical scenarios. First, you're in the studio and recording a band — say eight channels for drum mics, four for guitars, plus another four for piano and vocals, all connected to channels 1-16 of the ZED R16. In your DAW you'd set up whatever combination of mono and stereo tracks you fancied to handle these 16 inputs. Meanwhile, on the ZED R16 you could set up a control-room mix on the main faders, and two separate studio headphone monitor mixes using the pre-fade aux sends 1 and 2, going via the dedicated Studio 1 and 2 monitor feeds. Nothing you do to set up the control room and headphone mixes affects the signals being recorded by the DAW, as these are sent pre-fader. However, you do get to choose whether the DAW feeds pass through the ZED R16's EQ and inserts or not — on channels where none of the four digital routing buttons is engaged, the feed is immediately after the preamp and high-pass filter, but on those where 'DIG SND Post-EQ' is engaged, the feed is after the EQ and insert point.

In the master section, some of the traditional mixer controls have been traded for a selection of MIDI controllers for use with your DAW, but you also still get plenty of more conventional analogue mixer facilities such as talkback, auxes and multiple monitor feeds.Photo: Mike CameronAfter tracking your band, you might choose to mix in the DAW, in which case you could set your DAW master fader to output to the ZED R16's 'Dig Master' (which replaces the main L-R bus) or simply to a pair of mono channels. Either way, you'd be monitoring your stereo DAW mix and could use the ZED R16 to route it to a two-track recorder or even back to the musicians in the studio via the studio monitor feeds. However, if you were to configure your DAW tracks to output to their corresponding channels on the ZED R16 you'd quickly have your mix on good old-fashioned analogue faders. You'd engage the 'Dig Ret Pre-Ins' buttons on all channels to get the Firewire channel feeds to replace the preamp signal, and the result would be a true analogue-summed mixdown from your DAW, with the further option of using the ZED R16's EQ and insert points.

The second scenario is simpler but just as valid. This time you've taken the ZED R16 and a laptop to a gig which you're simultaneously going to mix to PA and record. You use channel faders to set up the live PA mix, going out via the Main L-R pair, while again the post-preamp Firewire feeds from each channel allow them to be recorded clean into the DAW, so they can be mixed at a later date. But you could also record the Main L-R mix for good measure, as a safety copy or to quickly dupe and sell to fans as they're leaving. The ZED R16's aux sends and/or studio monitor feeds can be pressed into service to provide on-stage headphone or foldback monitoring. And specific master-section features such as the option to replace the L-R (in this case PA) mix with the input from '2-track 1' allows you to quickly get tracks playing from CD or an iPod in between sets without tying up any input channels. The only potential drawback for live use is the lack of group channels: you couldn't group, say, all the drums to a single fader (not such an issue in the studio, where you can use the group channels in your DAW).

Often, though, all you need is a simple send to Firewire, or a return from Firewire, and setting this up is pretty intuitive, using buttons to determine whether or not the signal passes through the EQ. But there's more flexibility on offer: using various setups and routing combinations that are described in the manual you can, for example, send a signal out of the mixer, through your DAW and back (to apply DAW effects in real time) or, similarly, route a DAW track via a mixer channel's EQ.

ADAT

You can do nearly as much using an ADAT multitrack system with the ZED R16 as you can using a DAW, although you lose any feed directly to or from the Main L-R bus (just as you do at higher sample rates over Firewire). This just leaves you the normal routing options to and from the 16 mono channels, but that still gives you plenty of flexibility. Of course, there are no facilities for mixing or controlling the additional ADAT channels using the desk, so that's something that must take place in your DAW.

In Use

Turning on the ZED R16, it's immediately ready for use. The blue power LED and MIDI-section buttons light up, and an internal fan starts. Although this isn't completely silent, it's certainly quiet — about the same volume as my MacBook when idling.

Noise performance and dynamic range is excellent. Equivalent Input Noise for the mic preamps is -

Despite the DAW-oriented nature of the ZED R16, it still looks like an analogue mixer, and has high-quality mic preamps and EQ on the 16 mono channels.Photo: Mike Cameron128.5dBu for 60dB gain, and mix noise from the L-R bus with 16 channels routed is -84dBu. The A-D converters operate at 24-bit resolution, with a superb 114dB dynamic range (A-weighted), and the 24-bit D-A is even better, at 118dB.

Allen & Heath say the mic preamps are the quietest they've designed, and are based on those in their GL2800 and GL3800 live consoles. Like some notable high-end preamps, they use a symmetrical design with high-quality transistors, resulting in very low distortion and excellent transparency. I made recordings with my favourite Schoeps combos (CMC6 bodies with MK21 and MK41 capsules), as well as some AKG C414XLSs, and had absolutely no quibble with Allen & Heath's claims: the sound was transparent, authoritative and musically involving, and was certainly comparable with that delivered by my DAV Electronics preamps. The gain pots squeeze the last 10dB or so of gain into a few millimetres, so precisely matching quieter outriggers or room mics isn't as easy as with stepped designs — but it's not impossible, as it can be with much cheaper designs, and it's simply not an issue with 95 percent of the recording situations the ZED R16 is aimed at.

The EQ impressed me too. It was easy to work with for both gentle massaging and more drastic treatments. There was always a smoothness and integrity to the outcome, without the grain and harshness of cheap desk EQ, yet with the weight and presence that often eludes digital and plug-in designs.

I was bowled over by the carefully considered control room, monitoring and master section. The separate control room and phones level-controls are an essential feature, of course, but the mono fold-down and ALT speaker outputs are seriously useful and often not so elegantly incorporated. Integrated talkback is great for studio and location work, and the various two-track routings are very handy. And the usefulness of those dedicated studio monitor feeds cannot be underestimated: not only do they very simply meet one of the more irksome challenges of recording with a DAW (the quick setting up of headphone monitor feeds), but I like the fact that they're stereo and allow you to send the main mix to the musicians.

Quirks & Queries

Nothing's perfect, though, and there were some aspects of this console that I found less good. My number one gripe is that the stereo channels have no digital send options, other than by routing to the L-R mix — and even that's not possible with ADAT-based or high-sample-rate Firewire use, which cuts out the L-R digital send. An option was apparently considered in the design stage whereby stereo channels ST1 and ST2 could be routed first to mono channels 13 to 16, and then to the digital sends from there, but this wasn't implemented. It's not difficult to patch a stereo input to mono channels, but I missed any sort of direct stereo-channel digital sends, especially when working with synths.

The only trace of the ZED R16 on your computer is the presence of a control panel (above), allowing a few aspects of operation to be configured.Photo: Mike CameronIt's also worth noting that there are no dedicated Aux returns — in fact, perhaps it's partly for this purpose that the stereo channels were included. More concerning though, especially for those planning to use the ZED R16 for final mixdowns, is the lack of a 'Solo In Place' function. Sure, the PFL function does something similar, and its signal is at least sourced post-EQ and insert, but your only option to truly isolate tracks at their in-mix level and pan positions is to solo them on your DAW, or to mute all the other channels on the ZED R16.

The inclusion of MIDI control is a love-it or ignore-it feature. Personally, I like the fact that the fader assignments aren't configurable (see 'MIDI Section' box), as this keeps operation very straightforward and predictable, and most DAW mixers can easily tie in with the ZED R16's MIDI control through their 'MIDI learn' function. As with every other MIDI-based control surface in which the communication is one-way, though, integration is partial at best, and you can tie yourself in knots trying to establish a workflow that doesn't constantly jump between the mouse and faders.

For some users, the lack of word-clock input or output could be a problem too, as you're tied to using the ZED R16's internal clock at all times. ADAT sync is provided using JET PLL clocking and jitter-reduction technology, but that's it.

Finally, it would be remiss of me not to report one weird operational quirk that I noticed on the review model: channel 1's digital return from Firewire was about 20dB lower in level than it was on every other channel. I'm told that this might have been because the particular ZED R16 I reviewed had been used as a 'test-bed' model during the design, but whatever the reason, Allen & Heath assured me that shipping models don't have the same problem.

ZED Dead Good?

The ZED R16 is a bold and exciting move by Allen & Heath, and one which I think will be very much appreciated by many studio-based musicians and engineers, as well as those who work on location. Essentially, they threw away the rule book on what we've come to expect from either an analogue mixer or a Firewire audio interface, and have produced something in which the traditional roles of those two devices are beautifully harmonised.

For me, the key aspect of the ZED R16 that makes it really enticing is its impeccable audio credentials — it has first-class preamps, lovely (and defeatable) EQ, plenty of headroom, and good noise performance. This doesn't make it cheap to build, I'm sure, but means it can fulfil, admirably, a wide variety of roles both in and out of the studio.

Then there's the flexibility. I love the fact that the ZED R16 is still a really useful tool, even when its not within a mile of a PC or ADAT machine. But when you do hook one up you have a very capable and versatile system that can handle even quite complex studio and live recording situations while retaining an immediacy and tactile quality that I've never experienced before using any other audio interface. At mixdown, the ZED R16 effortlessly adapts itself to the roles of monitor controller, 24-channel mixer, or superb-sounding analogue summing box for your DAW... or even all three simultaneously.

Many prospective buyers will, of course, bemoan the lack of motorised faders, more extensive transport and editing functions, and plug-in control — and it's true that if you thought you'd be getting a Digidesign C24 on the cheap you'd be disappointed (although I have a hunch the ZED R16 might well sound nicer). Allen & Heath's line is that HUI-like control and integration with motorised faders was never part of the design brief, and would have significantly added to the cost. This may well be true, and my own view is that it would also have spoiled the purity and simplicity of the concept, making the ZED R16 a much more complicated device requiring ongoing firmware, DAW-driver and operating-system updates. As it is, it might not meet absolutely everyone's needs, but I personally find its straightforward nature and lack of LCDs and menus a refreshing change.

So it's hats off to Allen & Heath for producing a mixer that isn't afraid to buck the trend, can work with almost any DAW, and puts audio quality and flexibility right at the top of the agenda. This is one of those great bits of gear that's genuinely worth aspiring to. It may not be cheap, but it's worth every penny — and like anything good you'll probably never regret buying it. Twenty years down the line, it could easily be earning its keep, even when ADAT, Firewire, and the current crop of conventional audio interfaces are no more than a distant memory.