A triple threat in powered speakers
By Jon Chappell
Senior Editor, Harmony Central
The KW series is the latest in QSC's active speaker series, with the 153 being the largest in the line, a 1,000-watt three-way system with extensive features. A pair of KW153s would be perfect for a pro-level DJ, a worship installation, an ensemble of any size performing in medium-sized clubs and larger, or for anyone needing a full-range system with self-contained power, multiple input options, and even mixer capabilities. If you're stepping up from a personal P.A. or need more functionality from your powered speakers than most other systems can provide, you can't do better than a set of the KW153s.
The QSC KW153 is a powered three-way system, with 15" low-frequency and 6-1/2" midrange cone transducers, and a 1-1/2" high-frequency compression driver. The cabinet is tall and slim, and tapers inward as it goes from front to back, making it easy to fit on a crowded stage. It stands on its own just fine, or you can mount it in the usual ways (on speaker poles or suspended above the audience – even upside-down).
Externally, the KW153 is comprised of a sturdy rigid birch plywood enclosure, covered completely in the front by a sturdy black steel grille. The cab has two cast aluminum handles on the sides that are flush with the surface, placed well, and feel comfortable in a full four-finger grip. Though the speakers weigh about 80 pounds, they're easy to manage in a two-man carry, even on a narrow staircase, because of the slender build and logical handle placement. There are eight M10 rigging points for suspending the speakers over the audience, and a standard 35mm socket for pole-mounting applications. (The smaller KW152 and KW122 also feature QSC's Tilt-Direct™ pole mounting system.) A small multi-function LED on the bottom of the front provides various status information (more on this below).
The ins and outs
The back panel has extensive routing and signal-processing capabilities. There are two simultaneously available channels, A and B, both sporting combination XLR/1/4" input jacks. Channel A, being the Mic/Line channel, has a 4-position input sensitivity control; Channel B has additional Left and Right phono inputs. Both channels have discrete XLR direct-output jacks for parallel, or Thru connections of the input signal to another speaker or other device. Each Channel has its own gain control and both can be summed to an additional XLR post-gain jack. If you're a DJ or smaller act that needs only three inputs to the P.A., you won't even need a mixer, as all three inputs can be used simultaneously.
The excellent design of the KW153 continues inside the physical structure, tucked into the electronics of the cabinet. DSP (digital signal processing) circuitry enhances and prepares the signal in many beneficial ways. Chief among these processes are excursion limiting (which prevents the woofer from traveling too far from accidental overloaded signals) and Intrinsic Correction™, a set of signal-processing algorithms that favorably corrects transducers and waveguides toward a more musical purpose.
In addition to these "behind the scenes" operations that protect and enhance the signal, the KW153 also offers user-controlled DSP functions. A switchable low-frequency setting allows you to optimize the crossover for either stand-alone operation or use with a subwoofer (like the KW181). If you're using the 153 without a sub and want the extra oomph of a stand-alone subwoofer-like response, you can invoke the LF switch's DEEP™ (Digital Extension and Excursion Processing) function, which provides increased low-frequency extension without distortion or woofer over-excursion.
For the high end of the spectrum, the KW153 offers two different settings, Flat (for a non-colored, neutral output) or Vocal Boost, which engages an EQ circuit specially designed to enhance vocal presence and intelligibility. This is great for situations where you need to plug the mic straight into the cab, as in the case of a quick-'n'-efficient setup for a solo act or duo, presentation or house of worship. As an added bonus, the KW153 includes a socket for an optional remote mute/gain attenuator controller, plus a three-way function switch (Off/Limit/Power) for the front LED, giving you the choice of seeing the status for Standby/On or whether any of the Limiter circuitry is active. This lets a house sound person know what's going on with the system at a glance.
I brought the KW153s on my duo gig, even though it was overkill for the amount of output available. Still, the KWs managed the sound better than any two-way system I've used, regardless of power. The three-way frequency treatment uniquely allowed my partner's acoustic bass to live in its own world. A working DJ I know put the KWs to the test by pumping through massive amounts of dance and techno program material. We both had the same reaction: that the sound was loud and extremely clean and focused. My DJ friend singled out the bass response from the 15" woofers and the crossover performance as "totally delivering" and even "raging," and said that it will make him rethink his approach of toting a separate subwoofer to every gig. Having the midrange 6.5" speaker would also be ideal for live bands, especially with horns.
Physically, I particularly liked the KW153's combination of efficient cabinetry and even dispersion pattern (75 degrees at all frequencies), as they played well with other onstage objects in tight quarters and offered a full sound that belies their slender stance. Plus, the extensive feature set, including the DSP functions, will in many cases eliminate the need for a separate signal processor, mixer, or both. That, combined with a thousand watts of lightweight yet robust Class D power powering a three-way system affords you the volume and versatility you need for just about any gig or installation.