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Amazingly powerful output and killer sound in a compact cab.
The QSC K12 is a 12" 2-way PA speaker system boasting a 1,000W Class D power module and ~75° horizontal and vertical coverage. Low frequencies extend to ~48Hz (-10dB high acoustic output, 131dB peak). This low-frequency extension makes the QSC K12 an ideal choice for music playback and live reinforcement of instruments, especially in venues where more directional speakers are needed. Equally at home in the role of stage monitor, the QSC K12 speaker enclosure has an angled side for use as a low-profile, horizontal wedge and a flat side for proper side-fill use.
QSC's K12 PA Speaker features a 1-3/4" HF device in its 2-way enclosure. The primary differentiator in K Series speakers is the resulting output dispersion—the K8 being the widest at 105° and the K12 the narrowest at 75°. This radical approach is achievable due to a process called Directivity Matched Transition (DMT). DMT allows QSC to take advantage of a fundamental law of acoustics: smaller diameter woofers have wider coverage patterns than larger ones. The K Series matches the HF device to the LF dispersion, allowing for the smoothest and flattest frequency response possible across the entire sound field.
Add to this advanced DSP processing and an enclosure molded from ABS—a material far more rugged and sonically pleasing than conventional plastics—and the QSC K12 delivers exceptional performance in this category of loudspeakers.
Several proprietary QSC DSP technologies are incorporated into the K Series. One such technology is Digital Extension and Excursion Processing (DEEP). DEEP allows each of the K Series models to deliver levels of low-frequency extension previously impossible in enclosures of this size. Intrinsic Correction, first featured in QSC line-array technology, use dozens of spatially averaged measurements mapped to the processor to deliver smooth and accurate reproduction across the entire sound field.
Preventing amplifier clipping or overload is QSC's proprietary GuardRail technology. GuardRail closely monitors the input voltage and controls the amplifier output stage before the onset of clipping. Unlike typical clip limiters, when GuardRail is activated, the results are all but undetectable—there's none of the typical "pumping" associated with other methods. In addition, user EQ controls are provided to select between subwoofer settings (EXTSUB, VOCAL, or FLAT response).
The K12 speaker boasts other user-friendly features. For example, when the speaker is pole-mounted, the Tilt-Direct pole socket converts to a 7.5° down-tilt with a simple 180° rotation of the dial. A locking IEC power cord is included, preventing accidental disconnect during a performance. For installed applications, connecting a commonly available potentiometer to the unit's Euroblock connector allows the operator to have gain control from a remote location. Multiple K Series units can be daisy-chained together to one centralized control. Additionally, the K Series enters Standby mode after 5 minutes of inactivity, conserving power.
The entire QSC K12 package is housed in rugged and sonically friendly ABS (the sub in birch plywood) with steel grilles and easy-carry ergonomic aluminum handles.
Processing, Connectivity & Monitoring
The brain of the system is its expansive digital signal processing. While the DSP functions are optimized using Intrinsic Correction, DEEP, DMT, and GuardRail technologies (with the high-pass filter included for use with subwoofer systems), two XLR-combi inputs, each with its own Level control, are provided. Both accommodate line-level inputs and one may be switched to microphone level sensitivity. Phono (RCA) input jacks are also included for connection of consumer electronics sources. Dual XLR outputs are provided for dual "loop-thru" XLR/M connectors and a single XLR jack is available as a summed output. All 3 input sources may be used at once and mixed via the 2 Gain control knobs.
Input Panel LED indicators are provided for Power, Signal Present, Mic Level Sensitivity, and Limit annunciation. A front-mounted power LED may be disabled by means of a
rear-panel switch when desired or set so it indicates when the limit circuitry has been engaged.
Waveguide
Each K model incorporates a conical waveguide that maintains pattern control all the way down to the crossover frequency. The coverage angles of the waveguides are tailored for a smooth transition from woofer to compression driver with far less "waistbanding" or other directivity related anomalies than other products in this class.
Suspension and Mounting
The K12 2-way PA speaker may be pole-mounted, suspended, or yoke-mounted. The K12 yoke accessory kit (not included) allows for either horizontal or vertical yoke mounting, providing a flexible means of attaching K Series loudspeakers to a building structure or truss. When suspended deployment is required, M10 threaded inserts support vertical or horizontal suspension, while the integral polemount socket accommodates 35mm speaker poles for use on a speaker stand or over a sub. The pole socket is designed so that the speaker may be angled down 7.5° in order to cover the audience while keeping acoustic energy off reflective walls and ceilings.
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