HK Audio ConTour

The CT 112 and CT 115 high/mid cabinets incorporate HK’s newly designed 60 x 40 degrees CD horn, enabling them to be clustered in multiples without phase issues. In smaller venues, the front-ported, two-way cabinets can actually be used ‘full range’ without the use of a separate subwoofer, which is also good news for bands or hire companies needing a scalable system that can be adapted to suit various venue sizes and SPL requirements. The tops are even designed to double as stage monitors, and the CT 112 and CT 115 have switchable internal passive crossovers, enabling them to be used either passive or bi-amped, and where necessary the CD horn can be rotated through 90 degrees with minimum fuss for horizontal monitor use. HK’s now familiar TripleTilt pole mount is standard on the CT 112 and CT 115 to optimise the vertical coverage angle by allowing the user to choose from three tilt angles. This is achieved by means of a pole socket with three apertures, and you just pick the one that best suits the purpose.

The CT 118 active sub utilises a single SICA 18-inch driver and incorporates a 56-bit digital system controller plus two 1000W RMS PWM (Pulse Width Modulation) Class-D power amplifiers to deliver maximum power with minimum weight. One of these power amps drives the subwoofer speaker, while the other powers an 8Ω top, which can be a CTA 208 mid/high unit or a ConTour CT 108, CT 112 or CT 115. The DSP system controller stores personalities for these different cabinets so that the correct crossover and power limiting characteristics can be selected for whichever top box is used. An integrated display shows all the relevant setting information and also allows the relative level of the sub to be adjusted. To protect the electronic components from excessive vibration, the circuitry is shockmounted on rubber grommets, and both thermal and short circuit protection is built in.

The connections are fairly conventional, with linked male and female XLRs to provide input plus output link facilities, these being electronically balanced and floating. A Speakon NL4 feeds the mid/high top box, while mains comes in on a Powercon with a corresponding Powercon power link out socket. There’s also an RS 485 Ethercon connector for linking multiple cabinets so that changes made to the controller settings on one of them are transferred to all the connected boxes. Currently, there’s no provision for setting up via a computer.

HK have tuned the cabinet to give what they describe as a tightly defined, punchy bass sound, which suggests a reasonably well-damped design, the specified LF frequency response being 3dB down at 42Hz and 10dB down at 36Hz. With a sensitivity of 100dB for 1W@1m, the speaker is very efficient and has a maximum SPL of 131dB peak.

Clearly, a box housing this much bass-end power needs to be very rigid and free from elements that might vibrate, so HK have used 18mm, 13-ply birch plywood, finished in a tough, textured polyurethane coating. The driver is protected by a metal grille with a thin layer of acoustic foam behind. There are handle grips routed into the side panels (three per side), which is always preferable to separate hardware that might rattle, and there’s an integral M20 thread pole-mount point in the top. However, only one end of the cabinet has a handle, so lifting through narrow doorways that incorporate a step can be fun!

Despite its impressive credentials, the sub weighs just 42.5kg, making it a practical two-man lift. But to aid transport and to provide protection while in transit, the sub also comes with a dolly board fitted with heavy-duty castors, which shields the rear panel. Overall, the sub measures 500 x 680 x 600mm, which is reasonably compact given its capability. Protective covers and stack plates for use in multiples are available as optional extras.

Other than the handle placement when it comes to narrow doorways, the only negative observation I have is that the sub is only designed to drive a single 8Ω top box rather than a pair — something that might have been useful in smaller venues. This might have been less limiting if the sub at least offered a line-level output after the DSP crossover/processor so that a high-pass filtered signal could have been fed to one or more additional active tops, but it seems the HK stance on this is strictly one top box per sub.

The CT 112’s internal passive crossover operates at 850Hz, although this can be switched out for active bi-amping should that be desirable. A nominal power-handling figure of 400W RMS is quoted with a short-duration, maximum peak capability of up to 1800W. The frequency response is 80Hz to 16kHz between the 3dB down points, while the sensitivity is very high at 107dB for 1W@1m. A maximum peak SPL is specified as 134dB for 10 percent THD over the frequency range 200Hz to 5kHz.

Each cabinet has a pair of Speakon NL4 connectors to facilitate linking, and like the subs, the boxes are very robustly constructed from 8mm, 13-ply birch plywood. The asymmetrical rear angles mean the cabinets can be used as floor monitors at angles of 47 or 18 degrees, and again carry handles are routed into the woodwork, this time top and bottom. As with the subs, the finish is a black acrylic lacquer and the metal speaker grille is backed by a thin layer of acoustic foam. For rigging, the cabinet has Aeroquip fly tracks and a pair of M10 threaded bushes in addition to the TripleTilt pole mount, offering angles of +5, -3 or -10 degrees. While the multiple pole-angle system is a great idea, I would have preferred one of the positions to be level.

These cabinets feel very substantial, weigh 25kg and measure 380 x 335 x 610mm. Optional accessories comprise a mounting yoke, M10 eyebolt and a protective cover. All the published specs assume half-space operation, so the maximum SPLs will be slightly less in an outdoor situation such as the one we used for the test.

In the acoustic tent opposite, we used a combination of HK Premium PR:O and Fohhn components, augmented by Alto and Mackie speakers around the edges to push some of the sound out into the field for the benefit of those sitting outside. This worked out extremely well, with plenty of low-end capability for those acts with electric or upright basses. The plan was to alternate acts between the two stages so that there would be no dead setup time, and amazingly, everyone started and finished on time.

Once everything was set up, we ran an initial soundcheck using test material played back from an iPod and adjusted the sub level to give a good subjective balance, which ended up being -4dB or -5dB. The fidelity of the sound was extremely good with a generous but well-controlled low end and a clear, detailed mid-range, but what really surprised me was how well the sound carried to the acoustic/beer tent at the opposite side of the field some 70 or 80 metres away, despite these being promoted as short/medium-throw speakers. Essentially, the stage was looking across the rectangular field, and we weren’t too worried about having a very wide horizontal dispersion, as there were other events going on at the ends of the field that would benefit from a reduced sound level.

Having tested the speaker system and line-checked the mixer inputs, we got on with the business of miking the bands, and it soon became clear that this system was going to have no trouble at all handling the job. The maximum volume was probably limited more by the vocal-mic feedback threshold (which was actually pretty high) than by the system’s power capacity. Of course, the weather wasn’t going to let us have all our own way, and despite the ‘wall to wall’ downpours predicted by the BBC weather forecast being commuted to occasional heavy showers, we ended up working with thin plastic bin liners taped over the tops and sidefills. We’re always complaining that the council have made the bags so thin now that the rubbish falls straight through the bottom, but from an acoustic viewpoint they could hardly have been better and the sound was barely compromised. During the heavier showers, those without umbrellas retreated to the beer tent and listened from there, which is where the throw of the system was really appreciated. The tonal balance also held up well with distance, so the bands sounded good almost regardless of where you stood in the field.

Last year, we used an excellent Fohhn system with a similar spec and of a similar price. Overall, I’d say the performance was pretty comparable, but with the slightly tighter dispersion angle of the HKs giving perhaps a bit more throw at the expense of a little horizontal coverage. In most venues, the HK ConTour rig will enable you to direct most of the sound where you want it, though any general-purpose speaker design must necessarily be a compromise, which is why in larger touring systems different speakers are used for short-throw and long-throw coverage. The HK system’s dispersion characteristics make it about as flexible as a one-size-fits-all solution can be. The combination of German design engineers and high-end Italian drive units certainly seems to be a winning formula, and to have a system that can fit into an estate car yet also handle a reasonably large outdoor event such as West Fest is nothing short of spectacular.

As commented upon earlier, the scalability of the system would have been improved if the subs had line outs from the DSP crossover to allow additional active speakers to be added without also having to add an additional active crossover or system controller. To be fair, the Fohhn system we used last year also lacked filtered line outputs (and I whinged about that too!), but their active sub can drive two passive tops in stereo, so there’s a bit more flexibility there for playing smaller venues where only one sub is needed. The HK system is also a little heavier, but you get a great deal of performance, both in terms of quality and quantity, from what is, in reality, still a very compact and very manageable system. The cost may seem on the high side when you look at the size of the system, but it’s certainly more than reasonable for the performance on offer, and if you have an estate car, you might just save yourself the cost of a van!  0