Slate Raven MTX

Few product launches have attracted as much attention as Slate's touchscreen controller. Is the Raven the future of DAW control — or an oversized iPad?

Back in the 'glory years', making records was a much more physical experience than it is today. Every recording studio had a big mixing console — size really mattered back then! — and the process of mixing often involved not only the engineer but also the producer, and sometimes even several members of the band as well, just to be able to operate all the knobs, buttons and faders at the right time! The tactility of the controls was important, as was the entire ergonomic design, and engineers chose one company's console over another's in part because of the way it felt to use.

Today most of that has gone, replaced with a bland, generic mouse and computer display screen. Of course, this arrangement works well enough for most of us, and is certainly a very cost-effective and versatile interface, but the grandeur is missing. The ergonomics are generally atrocious, too, and there are significant operational limitations: a mouse can only be moved by one person, and it can only move one knob, fader or button at a time. Thank heavens for automation!

For some, these limitations are unacceptable, and the only practical solution is the reintroduction of some form of hardware controller to allow multiple physical knobs and faders to be operated simultaneously, with real-time tactile feedback. However, such controllers aren't as versatile and configurable as a 'virtual console' on a computer screen… and that's where the Slate Pro Audio Raven MTX Multi-Touch Production Console comes in.

Rapid advances in touchscreen technology for phones and tablets have made us all very familiar with the idea of jabbing and swiping our fingers across a screen to make something useful happen. Indeed, the whole touchscreen paradigm has quickly become a very instinctive and direct way of controlling apps, and the ability to change what appears on the screen from moment to moment makes this an incredibly flexible and powerful technology. The touchscreen concept has already spread into the laptop and desktop computer world too, at least on the Windows side of the argument, with Windows 8 supporting touchscreen functionality. All of the major software manufacturers must already be beavering away to develop touchscreen versions of their products. The touchscreen and the DAW make ideal bedfellows, and several manufacturers have already adopted the iPad as a versatile remote control surface for this kind of application.

Steven Slate's vision for the Raven MTX employs exciting, cutting-edge technology to take the concept of a touchscreen controller to a whole new level of physical interaction which will undoubtedly influence the future of the DAW for all of us. I imagine Slate Pro Audio will face stiff competition in the years ahead, but they are the only runners at the moment and their direction is being shaped and guided from the front: Slate himself is a demanding end-user as well as a technology pioneer.

Multi-Touch

Slate Pro Audio's new flagship Raven MTX, exalted as the world's first Multi-Touch Audio Production System, is designed to "remove all obstacles” between the engineer and DAW. It allows the user to interact directly and immediately with the DAW through the touchscreen, using multiple fingers to drag multiple faders simultaneously, to adjust virtual rotary controls and buttons as if they were real physical objects, and to move and shape audio clips and automation data precisely and instinctively. Having spent several hours now using the Raven MTX myself, I can say that it really does manage to achieve all that in a pretty convincing and surprisingly usable way — and that's from someone who was extremely sceptical about it beforehand!

The proprietary core technology of the Raven MTX combines both hardware and software elements. The hardware integrates a large, 46-inch, high-definition LCD touchscreen into an angled console in such a way that the user sits in front of it and controls the virtual on-screen mixing desk almost as if it were a real, physical desk — this is a truly 'hands-on' interface. It's worth noting that designing a touchscreen of this size is far from trivial, because conventional technologies can't be scaled up easily to these dimensions. Resistive and capacitive touchscreens are just too slow and impractical for this kind of application at present.

Instead, Slate had to develop a bespoke system employing a commercial-grade, LED-backlit, in-plane switching LCD display screen. This is a full 1920x1080 (2k) HD display which sits behind a 2mm protective glass surface coated with a proprietary 'nano-surface' treatment to ensure the user's fingers slide smoothly and consistently across the surface. (The display screen can be upgraded fairly easily when 4k or 8k resolutions become the norm.) The multi-touch sensing system is implemented using a front-mounted optical sensor array, which generates a grid of infra-red beams just above the glass surface. This is capable of detecting and tracking 12 simultaneous touch points with a very fast 5ms response time, which is critical in preventing any sense of lag or 'disconnection' when using the touchscreen. The MTX touchscreen is connected to the host computer using DVI for the video display and USB for the control data.

The Raven Mixer utility is an 'overlay' that translates multi-touch gestures into control messages that a DAW can understand. A nice touch is the inclusion of visual track identification icons, as are being chosen here.

Tablet or smartphone users will be aware of the streaks and smears that quickly build up on their screens, but the Raven MTX doesn't appear to suffer to anything like the same degree, and I think this is, in part, due to the bright and light-coloured mixer graphics (smears tend to show more clearly on dark backgrounds). The surface also feels smoother, with less noticeable friction than any tablet I've ever used. Of course, the screen does need regular cleaning, but I gather that the demo models are typically cleaned only once a week — there was certainly no obvious need to clean it after I'd been using the MTX for several hours. A bottle of the nano-glide surface treatment is included with the MTX to re-treat the screen, but I imagine this would only be a quick monthly routine for most users.

At the moment, the Raven MTX is only compatible with Mac computers running OS 10.7 or 10.8, but any current Mac Pro, MacBook Pro or iMac should be suitable. As you would expect, the display image is crisp, detailed and bright, with a very wide viewing angle, no obvious parallax issues (provided the user runs a brief touch-calibration routine as part of the installation), and negligible radiated heat, thanks to the cold LED backlighting. There are no cooling fans in the Raven MTX console, either.

Monitoring

Enhancing the practical usability and workflow aspects of the Raven MTX system, the physical console also houses the unavoidable keyboard and trackball, plus a comprehensive monitor controller (supporting up to 7.1 surround), with full cue and talkback facilities. The hardware console is a substantial free-standing chassis and, usefully, Argosy are intending to produce matching sidecar furniture to accommodate other racked studio equipment, if required. The Raven MTX is available in both stereo and 7.1 versions, and the stereo model can be upgraded to the full 7.1 spec subsequently, if required.

Four pairs of VU meters across the top of the MTX console indicate the output levels, with a pair of Apple laptop-style reference speakers also embedded in the meter bridge. Slate refer to these as 'Betty monitors', and they provide 'grot-box' reference monitoring. An illuminated blue Raven bird logo in the centre of the meter bridge turns red whenever the talkback is activated, which is a nice touch, while down on the arm rest there are ports for connecting an iPhone and several USB dongles or pen drives, along with headphone outputs. In other words, everything you are likely to need has been neatly integrated into one comprehensive and ergonomic workstation.

The arm-rest monitoring controls and buttons are actually digital remotes for the very high-quality, all-analogue, monitoring controller electronics housed in a separate rack module mounted at the rear of the MTX console frame. The monitoring audio I/O is accessed via a pair of DB25 connectors providing eight balanced analogue inputs and outputs, and there is provision in the racking to accommodate a computer audio interface of your choice directly alongside the Raven's monitor section electronics. The review system was set up with a Pro Tools HD Omni I/O interface here, for example (although I wasn't too impressed with the resulting fan noise!).

Raven Mixer

The bespoke multi-touch display is only part of the Raven MTX system, though, because current DAW GUIs just aren't designed for multi-touch control: they are all intended to be used with a single mouse pointer operating one on-screen item at a time. Consequently, the mixer windows in existing DAWs are not able to take advantage of the Raven's multi-touch capabilities directly.

The Raven can be used to control any Mac program, although you won't get the benefits of multi-touch unless that program supports it directly. Here, the Pro Tools Edit window is displayed above a couple of Raven customisable toolbars.

Fortunately, however, multi-control operation of DAWs is possible through external hardware surfaces, communicating via interfaces like the HUI or Eucon protocols. So to realise the Raven MTX concept, Slate's team had to develop their own 'universal' multi-touch virtual mixer software, and equip it with the means to translate multi-touch actions into a form that a DAW can implement. The resulting Raven Mixer application employs a custom-built version of Paul Neyrinck's V-Control interface to act as the bridge between the Raven Mixer multi-touch surface and the DAW proper, essentially using four MIDI (HUI control) ports via a USB connection.

As you might expect, the Raven Mixer program is a very flexible and fully equipped virtual mixing console, replicating the full range of generic mixer features provided by any DAW. There are 32 on-screen faders, complete with automation mode displays and functions, rotary pan and send controls, track arming, mute and solo buttons, plug-in access, and so on. The layout is instantly recognisable to anyone familiar with traditional hardware or virtual mixer paradigms.

The mixer is actually constructed in two sections, with the faders, automation modes, track arming, mute and solo and plug-in access controls in one part, and the aux sends or channel metering in the other. These two sections can be swapped over by simply dragging them around, so that if you're mixing you can have the faders at the bottom of the screen in easy reach, with the meters or send controls at the top. Conversely, if you're spending time setting up or adjusting the cue and effects sends, you can drag that control section closer and push the faders out of the way to the top of the screen instead. This is a nicely thought-out detail that minimises unnecessary stretching and avoids the fear of developing 'gorilla arms'! Using the console continuously for a couple of hours, I found no problem in this respect at all, and the angle of the touchscreen seems perfectly judged, to me.

It is also possible to switch off the send/meter section to reveal the DAW's timeline and waveform display below. This allows you to watch the audio clips pass the replay 'head' while you mix, or you can zoom and scroll horizontally or vertically to examine a clip, adjust its position or modify the automation nodes just rby eaching out and dragging your finger as appropriate. All of the DAW's normal editing functions can be controlled through the touchscreen too, using a single finger just as you would a mouse — but in a much more direct way.

Accessing and controlling plug-ins works in the same way as in any DAW, but on the MTX screen, graphical emulations of vintage plug-ins are roughly the same size as real 19-inch rack devices! Few plug-ins are coded for multi-touch control yet, but I imagine a lot soon will be, at which point controlling them through the screen will become a lot more lifelike and interactive.

In addition to standard mixer facilities, the Raven Mixer incorporates customisable toolbars, the first of which is normally anchored to the base of the screen beneath the faders. This 'panel' would normally contain the DAW transport controls, fader banking and paging buttons, and file management facilities, plus key waveform editing modes and functions, record-looping, click on-off, grouping controls and any other DAW functions that might be needed for a given situation. Specific sets of controls and tools can dragged into any number of selectable 'panels', which can then be displayed or hidden as needed. Unlimited arrays of user-programmable macro keys are also available, so that the Raven Mixer can be customised to suit personal preferences and workflows, and all layouts and configurations can be saved and recalled to the DAW.

When displaying the DAW screen, waveform and track zooming as well as scrub/shuttle and track banking commands can all be performed using one- and two-finger swipes and gestures — left-right and up-down — on a small 'Nav-Pad' section of the toolbar. For more precise control, a much larger, semi-transparent Nav-Pad is also available, which can 'float' on top of the DAW or Mixer display. A large semi-transparent floating time display is also available.

The Raven Mixer software is relatively easy to update, and in the few weeks since my first seeing and using the Raven I've lost track of the version updates: new releases were being issued several times a week and most brought new or improved functionality, rather than just being bug-fixes! As a result, this is a case of 'moving goalposts', and many features will have changed or been augmented (dramatically in some cases) between my writing this review and the first public release versions.

It may be obvious, but the Slate Pro Audio team started the Raven MTX project with music production foremost in their minds, and the functionality and ergonomics were initially slanted in that direction. However, as soon as pre-production prototypes became available, Slate Pro and their distributors started demonstrating the Raven MTX widely throughout the industry, inviting not only professional recording studio engineers, producers and musicians, but also post-production companies and college staff to help assess and evaluate the product. That on-going exercise has gathered an enormous amount of feedback and copious wish-list requests, many of which has already been incorporated to expand functionality and improve the MTX's usability for the widest possible market.

The Raven MTX is very much a continuing 'work in progress', but even so, the pre-release software I was using was fully functional, totally stable, and wonderfully intuitive to use. Development will continue in the weeks, months and years to come, but the Raven MTX is already a surprising and delightfully usable mixing and editing platform.

User Impressions

When I first heard of the Raven MTX, I was rather sceptical, and thought it would be little more than an oversized iPad remote controller that would deliver a sun-tan and curl your hair for free while you mixed! However, I'm very pleased to report that the reality is very, very different, and that while the MTX won't suit every pro-audio role, it does offer a substantial improvement in workflow and ergonomics for many DAW-based applications.

Plug-ins can be called up and adjusted directly from the Raven Mixer overlay.

Let's deal with the obvious concerns first: despite the large size of the screen, you definitely won't get heatstroke after hours of mixing, because there really is no discernible heat at all. Moreover, having used it for several hours at a stretch, I can report that I didn't find it fatiguing on the eyes or the arms. This last point came as a great surprise, but the angle and height of the screen seems to be perfectly optimised so that moving faders, operating buttons and rotating control knobs all felt very comfortable and natural. It was certainly no harder or more straining than working on a conventional hardware console. Of course, it was a bit of a stretch sometimes reaching for controls at the top of the screen, but no more so than on any hardware controller or console — and the beauty of the Raven MTX is that if you need to reach those distant controls a lot, you can easily drag them into closer reach!

The act of touching the things you're looking at, rather than remotely guiding a mouse pointer, makes you feel much more intimately involved with the whole music-production process. Like most people, I've used tablet-based apps a lot, but the sheer scale of the Raven MTX takes that human-machine connection up to a whole new level. It's quite hard to express on paper, but it becomes immediately obvious when you try it for yourself. All I can say is that it felt like a very natural, very comfortable, and extremely immediate and responsive experience to be controlling the virtual mixer and operating the DAW through the Raven MTX. Moving back to traditional mouse-control afterwards felt cumbersome, indirect and intrusive.

However, having spent my formative years sat behind mixing consoles staring at moving TV pictures, I can vouch for the importance of being able to feel your way around the faders, so I don't think the Raven MTX will suit that kind of live-mixing-to-picture application. Nevertheless, it will be useful in post-production track-laying, great in radio production, and very popular in music studio production, obviously.

The Raven Mixer software has a lot of lovely features and functions that make it a joy to use. For example, you can touch the mute button on one channel, and then drag your finger across the mute buttons on any number of other channels to mute them all — detouring around the mute buttons on channels you want to remain active — and the same idea works for the Solo function too. Also, once you have touched a fader, your finger doesn't have to stay precisely over the knob to control it; you can slide your finger away and as long as it remains on the glass, any vertical movement will move the fader correspondingly. Creating fader groups is as immediate as swiping across the wanted channels to select them all, and then pressing the 'create group' button on one of the toolbar panels. There are loads of simple physical short-cuts like this, with more being added all the time.

One particular benefit of the Raven Mixer is that it displays 32 faders at a time — more than the standard Pro Tools mixer window — and while there are toolbar buttons for scrolling or banking left or right, you can also use a two-fingered swipe on the Nav-Pad to do it instead. That kind of direct and instant control becomes very addictive, very quickly!

The multi-touch surface can also be used as a single-touch controller for normal computer programs, and it felt entirely natural and intuitive to open, configure, operate, and close other programs directly, to the extent that I wasn't even thinking about it after I'd closed down the Raven Mixer software! Where you conventionally recognise a button or box on-screen, guide a mouse pointer towards it, and then click on the remote mouse button to achieve the desired outcome, the Raven way is simply to poke it directly with a finger, and this instant simplicity has an astonishing effect on the way you think about and use the computer. It makes it a much more responsive, physical interaction, somehow, and I think the altered mind-set that results has a pronounced effect on one's creativity.

The Raven MTX won't suit every application — there is still a valid role for physical faders in some situations — but the nay-sayers really should try it for themselves before voicing an opinion, because I found the system surprisingly enticing and remarkably usable. The only warning I'd offer is that it is important to run through a personal touch-alignment routine so that the software recognises where you think your fingers are on the screen! Without this, you can find yourself stabbing at buttons but not getting the expected response because the software thinks you're pointing at something else. Having used the MTX for several hours already, I'd have no qualms at all about mixing a project with it tomorrow, and as you become familiar with the operation and the gesture short-cuts, it quickly becomes such a fast and direct way of working that it makes conventional methods seem positively outdated and obstructive. This is definitely a technology to watch, and the smaller MTi model (see 'Raven MTi' box) will be the way in for many project studios.