Physically, the DB4 shares the exact same dimensions as the 92, and it weighs in at two pounds less—which may not seem like a lot, but it feels surprisingly light the first time you pick it up. The layout is familiar—the DB4 has the same Xone knobs and the little metallic three-way toggle switches that have always felt too delicate for a DJ mixer (although real world experience disproves those fears). The multi-color LED meter on each fader is similar, but is helpfully stretched out to include more LED measurement points for more accurate metering.
The horizontal band stretching across the middle of the mixer is where things start looking a bit alien when compared to a traditional mixer. In the place normally occupied by EQs you'll find the FX and looping controls for each of the four main channels. Further off to the right edge of the mixer there is an impressive OLED display that provides a useful indication of track tempo and FX selection during normal use.
At the top of the DB4 you'll find controls that perform triple duties—three knobs that are switchable between normal EQ, isolation EQ and filter modes. In filter mode, you get one LPF, one HPF and the middle knob functions as sort of a parametric EQ control. This flexibility to handle pretty much any mixing style plus the fact that the illuminated color scheme of the three knobs lets you know instantly which mode each channel is in is a stroke of genius. The only downside to this arrangement is that due to the nature of LPF and HPF (where normal signal is at fully counter-clockwise and clockwise positions, respectively), switching between modes can result in jarring changes in the sound. Typically in these scenarios gear designers build in a "soft takeover" mode to prevent the jumps from happening and this is one feature that would be helpful as an option on the DB4.
As we continue up, the last controls at the top of the mixer are the input select knob / toggle switch combo that provides for up to twelve sources to be selected on any given channel (four analog, four digital and four USB). This "input matrix," as Allen & Heath call it, is incredibly powerful as it allows you to select an input source on more than one channel at once, applying different effect or loop settings to each and crossfading between the two.
Speaking of effects, each of the four FX units are stocked with a choice of five different effect types—delays, reverbs, modulators, resonators and damage—with each type having a library of effect variations selectable from the main screen of the mixer. According to Allen & Heath, the DB4's effects and internal processing borrow from the DSP science of their flagship iLive series. The iLive mixing systems can cost more than a modest house, so the fact that they adapted that engine for the DB4 should immediately settle any debate to the sound quality of this unit. To wit, we were initially disappointed to read that Allen & Heath replaced the analog filters of the 92 with a pair of digital recreations, but when we finally got our hands on it they sounded surprisingly good. The one improvement we'd like to see with the FX is some way of telling (on the OLED screen) what parameter the expression knob controls for each selected effect.
Finally, we reach the looper sections—one per channel—with an unassuming and sparse layout of one knob and an LCD. This may not look like much, but the placement and ease of use is the height of convenience. Loopers are becoming more and more ubiquitous in DJ gear these days, but the minimalist implementation of the DB4's in combination with the fact that they are always at hand right below the EQs makes them possibly the most useful of any we've tried.
Despite all of the incredible innovation and class Allen & Heath have built into the DB4, it's not for everyone. The physical design makes it clear that it's a mixer built to show off its fancy tricks, from the platinum-level FX and loopers to the switchable EQs—so if you're a let-the-records-mix-themselves purist you'd be better off putting your money towards the Xone predecessors like the 92. More importantly, the DB4's hefty price vaults it up into the category of luxury goods, reserving it as an investment for serious touring DJs or larger clubs who can afford the best of the best. For the rest of us mere mortals, who would welcome such an advanced mixer with open arms (could we afford it), the best we can do is hope that enough of the big names start putting the DB4 on their riders that it becomes an industry standard. Otherwise, start saving.
Ease of use: 4.5/5