Line array technology has been around for years but has only lately seen resurgence. Among the throngs of new line array speaker systems on the market is the second offering from Eastern Acoustic Works (EAW), the new KF760 series. The KF760 is a lighter, easier to fly, smoother response version fm its older brother, the KF860.
Product PointsApplications: Live audio, touring, medium to large venues
Key Features: Dual 12-inch woofers; dual 10-inch midrange drivers; dual 3-inch voice coil with 2-inch exit compression drivers; compact design; simplified rigging design
Price: KF760 – $8,167 KF761 – $7,334
Contact: Eastern Acoustic Works at 800-992-5013, Web Site.
+ Ease of rigging
+ Smooth sonic performance
+ Easier transport
– Not single-point flyable
– Tricky to fly in tight spaces
The Score: An overall success in every aspect. The EAW KF 760 and KF761 system is a giant leap in line array technology.
The KF760 series comprises only two loudspeaker cabinets: the KF760 long-throw module ($8,167) and the KF761 short-throw module ($7,334). Both modules are triamped/three-way designs. The KF760 is loaded with two 12-inch, low-frequency (LF) drivers, two 10-inch horn-loaded midrange drivers with an EAW Radial Phase Plug and two 2-inch exit/3-inch voice coil high-frequency (HF) compression drivers that are also horn-loaded. The KF761 is loaded identically with the exception of there being only one high-frequency compression driver, and
8-inch slot-loaded midrange drivers instead of 10-inch horn-loaded ones. The LF drivers are loaded into a proprietary bent-horn, with the horn mouths horizontally separated to the outside of the cabinet in order to provide controlled off-axis cancellations to match the MF beamwidth through the crossover region. The midrange drivers are coupled into a single large-format horn. The HF drivers are coupled to a HF horn coaxially mounted with, and extended by, the midrange horn. The KF760s have a horizontal pattern of 80 degrees with a vertical splay of 3 degrees while the KF761s have a horizontal pattern of 100 degrees and a vertical splay of 12 degrees.
Frequency response is measured at ± 3 dB from 80 Hz to 16 kHz on axis per box and can go down to 40 Hz in an array. The impedance per module/per driver is two times 8 ohms LF, 8 ohms midrange, and 8 ohms HF. A single KF760 (LF/midrange/HF) can produce SPL of 96/108/113 dB on axis at one meter with 1 watt. An eight-enclosure array can produce SPL of 106/125/117 dB with peak output of 154/169/156 dB on axis at one meter. Power handling in watts (W) for the KF760 is 2,000 W LF, 800W midrange, 300W HF; while the KF761 can handle 2,000W LF, 500W midrange and 150W HF respectively.
Rigging for the system is all new, and uses a captured hinge design, housed in high- strength tubular steel at the four corners of each module. Quick-release pins connect the modules at various angles and also lock the hinges creating a rigid array. The front hinge is designed to maintain a constant 1/4-inch gap between the cabinets regardless of the angle. This approach yields an additional benefit in that the KF760 arrays can provide radical curvature for down-fill coverage; even 90 degrees below horizontal without being pulled back over the stage. The system is also available with an optional dedicated caster pallet, which can hold four modules. The pallet measures 45 inches wide by 37.25 inches deep to form a standard road case size. Basically you can fit two sideways across a truck. This system used as a whole also allows for prerigging of cabinet angles (in sets of four) prior to the hanging of points at the venue.
Designing the arrays to fit different venues and coverage areas has also been made simpler with the KF760 Wizard. This downloadable program allows for optimal rigging configurations based upon the parameters that you choose, e.g., trim height, number of modules, coverage area, etc. All this so that flying an array is no longer a matter of guess work on-site, but a simple printout defining all angles and pinning points.
First things first – thank God this is nothing like the old KF860s! If anyone is familiar with the old pin-and-puck rigging system or how heavy the 860s were, you will be glad to know that this system is lighter, quicker and much more efficient.
The cabinet configuration that I used for this review was two clusters of four KF760s and four KF761s each. The first show out with the new EAWs was a corporate concert featuring Natalie Cole in Towson, MD. The indoor basketball arena was a good test for the whole package. Rigging was amazingly simple when utilizing the KF760 Wizard program. Effortlessly the cabinets rolled in on their custom pallets and flew straight up four at a time. I was a little nervous when the cluster leaned back to match the rear pin points of the following pallet, yet with a little ease the corresponding hinges were pinned and the rig flew as a whole. The flown system was accompanied by EAW’s new BH760 sub, comprising a double loaded 12-inch driver. The only interesting downfall of the KF760s versus the 860s is the fact that the latter, depending on the number of cabinets flown, could be hung from a single, center motor point whereas the 760s demand two points from a cluster that weighs less per cabinet (using a bridle single point suspension can be done – Ed.). This is due to the new “floating” pick points on the 760 bumper bar which allows you to adjust the initial angle of the rig from the first cabinet by moving the spreader (which holds the motor picks) on the bumper by pinning it to a series of 21 holes along the bar.
After the cabinets were in the air, the true test began. If I had to describe this system in one word, it would be “smooth.” No harsh tones rang out, no sharp piercing highs or over-barking lows, just a smooth curve. I was able to actually EQ the room and not the cabinets. When walking the room I found a superb evenness of the system. There were no holes or gaps found in a conventional speaker array. The sound level was consistent through the frequency range. When I was in the pattern it was like listening to a set of closefield studio monitors, but when I walked out of the pattern I was truly out of the pattern. The accuracy of the 761’s 12-degree vertical and 100-degree horizontal coverage pattern was simply breathtaking. Natalie Cole’s engineers were very pleased with the new rig.
The other profoundly amazing show utilizing the new rig was with the Baltimore Symphony Orchestra. This was an outdoor show on a football/track field. The arrays were flown from 34-foot scaffolding towers left and right of the stage. The short depth of the towers proved challenging when attaching the second set of four cabinets, due to the lean needed to connect the rear hinges. We overcame this by disconnecting and reattaching each cabinet separately so that the forward lean was minimized. Once wired, flown and with 45 inputs placed, the fun began. Again, the same qualities rang true, but this time outside and at greater distances then before. From one length of the field to the other (approximately 400 feet), the system sang with the personality of studio closefields. Smooth all the way, front to back. I was impressed with the dynamic quality and accuracy of the system. No subs were used in this application due to the system’s efficiency down to 80 Hz. The swells throughout Tchaikovsky’s 1812 Overture were reproduced beautifully, to be outdone only by the resolving fireworks display at the end.
Through every use of the KF760s I am awed by the ease of use and smooth performance. The rigging and design of the modules is superior in every way to its predecessor, let alone its weight and aesthetic beauty. Whether it is for a medium or large venue, touring act or simple one-off, this is the line array that you want in your arsenal.
Yamaha PM4000, PM3500, 02R consoles; BSS FDS-355 Omnidrive Compact, EAW MX8760 processors; QSC PL 6.0, 4.0, 3.4, BGW GTC amplifiers; Sennheiser MD 421,408, ME40, 60,80, AKG 414, D12, D112, C391, beyerdynamic M88, M160, Shure SM57, SM87, SM56, SM58, Beta57, Beta58, Beta87, and Countryman EM101 microphones; Countryman Type 85 DI box.