Item #: QSC KW181 LIST

QSC KW181 18 Inch 1000 Watt Active PA Subwoofer Loudspeaker

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Product Highlights

Product Description

Get ready to bring the bass! The QSC KW181 is a heavy-duty 18” subwoofer capable of pumping out some serious low end, powered by an imposing 1000 watts of Class-D amplification. The specs are rather impressive as well, with a frequency range of (-10 dB) 37 Hz to 129 Hz and a peak maximum SPL of 135 dB.

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QSC KW181 Loudspeaker Powered PA Subwoofer Features:

  • K Series performance in a lightweight, birch design
  • 1000 watt Class D power modules in all models (2 x 500 watts)
  • Extensive DSP featuring DEEP and Intrinsic Correction enhances system performance
  • DMT (Directivity Matched Transition) ensures uniform coverage across the entire sound field
  • Rugged, texture-painted birch enclosures
  • Four-position Mic/Line gain (full-range models)
  • Tour-grade 16 gauge steel grilles
  • Comfortable ergonomic handles
  • 35 mm pole sockets
  • Speaker mounting pole included (35 mm diameter, 36 inches (91 cm) long, M20 thread.)
  • M10 rigging points for suspended installation (full-range models)
The Enclosure
Weighing in at just 83 pounds and measuring a compact 20.1” x 23.4” x 29.9” (with casters), the KW181 outperforms speakers twice its size! Constructed of birch and covered in rugged texture paint (and with a tour-grade 16-gauge steel grille), the enclosure incorporates additional features that make the life of the working musician a little easier, such as comfortable ergonomic handles and a threaded 35 mm pole socket.

Back Panel
The back panel houses three important and very useful switches:

The MODE switch chooses between NORMAL and DEEP™ settings. The DEEP™ (Digital Extension and Excursion Processing) algorithm, a highly musical, non-distorting low-frequency EQ circuit, utilizes an integral Excursion Limiter to produce deep, thunderous bottom while protecting vital components. (See “Excursion Limiting” below.)

The POLARITY switch allows you to select NORMAL or REVERSE input polarity. This can be useful when mixing and matching with other brands of speakers, correcting “out of phase” anomalies due to bad system wiring or when addressing acoustic issues in a particularly challenging room.

The FRONT LED switch is helpful for monitoring how the speaker is functioning. It can be set to PWR, a simple way to know if the speaker is plugged in and turned on, LIMIT, where you can observe when the limiter is kicking in or OFF, disabling the front LED.

For inputs you’ll find a pair of combination XLR or ¼" phone (TS or TRS) jacks. Additionally, each of the two channels feature discreet female XLR direct outputs. The level at these outputs is identical to the corresponding input and independent of the KW181’s volume setting. There’s also a convenient Green LED to let you know when signal is present, very useful for diagnosing cable problems on a gig.

There is also a Gain control, offering up to +10db of gain.

More KW Series DSP
Juggling many functions, KW Series DSP (digital signal processing) circuitry enhances time alignment, limiting and protection, thermal management, and crossover functions. This allows you to keep the focus on your show without worrying about the status of your sub.

Excursion Limiting
The KW Series proprietary limiter averts woofer over-excursion (a major cause of sonic distortion, premature woofer fatigue, even burnt voice coils), by reducing harmful voltages without any audible loss, all while protecting the amplifier from overload.

Smart Features
KW Series speakers are fitted with a handy automatic Standby feature to conserve power and extend the life of your unit’s components. When there is no signal present, or if the Gain knob has been lowered to zero for five minutes, the green STBY LED illuminates and the amplifier drops into standby mode. When Standby is engaged, a small amount of flowing current facilitates an instant power-up, so the KW181 is ready to go when you are.

Don’t forget to cover up!
With a subwoofer of this caliber, you want make sure that it’s protected from dirt, dust, the elements, and the regular wear that occurs during transport and storage. The QSC KW181 Speaker Cover (sold separately) is weather-resistant, made of heavy-duty cordura nylon, and includes a convenient front storage pouch emblazoned with the QSC logo. Store your cables and accessories while protecting your KW181!
The QSC Family of Powered Loudspeakers and Subwoofers
When your goal is “accurate acoustical performance for the widest selection of applications”, it’s good to be QSC. Combining their expansive loudspeaker, amplifier, and digital signal processing know-how, QSC offers an extensive assortment of professional grade speakers, suitable for any purpose.

From the 8” 2-way K8.2 to the KLA line array models and everything in-between, all active speakers in the QSC lineup sport exemplary power modules, DSP and performance characteristics, ensuring parity amongst every enclosure in the line. QSC powered loudspeakers and subs exhibit a sonic uniformity and offer flexibility unmatched by any other professional loudspeaker manufacturer.

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Helpful Info about the Manufacturer
Phone:  800-772-2834 Warranty:  3 Years; 1 Year on TouchMix; CP Series warranty is 1 year +5 upon registration; B-Stock is 1 (one) Year only! Accessories: Limited 90 day

Product Specifications

QSC KW181 Loudspeaker Powered PA Subwoofer Specifications

  • Configuration: 18 inches subwoofer
  • Transducer:18 inches cone transducer
  • Frequency Response (-6 dB): 43 Hz - 97 kHz
  • Frequency Range (-10 dB): 39 Hz - 145 Hz
  • Maximum SPL (1 meter): 132 dB peak
  • Power Output: 1000 W Class D continuous
  • Input Impedance (ohms): XLR / ¼": 38k balanced / 19k unbalanced
  • Controls:
    • Power
    • Gain
    • LF Mode (Normal/DEEP)
    • Polarity (Normal/Reverse)
    • Front LED (On/Off/Limit)
  • Indicators: Power, Signal, Standby, Limit
  • Connectors: Dual balanced female XLR/¼" line level input, Dual Balanced male XLR full range line level out, Remote gain control, Locking IEC power connector
  • Cooling: On demand, 50 mm variable speed fan
  • Amplifier Protection: Thermal limiting, output overcurrent, overtemperature muting, GuardRail
  • Transducer Protection: Thermal limiting, excursion limiting
  • AC Power Input: Universal power supply 100 - 240 VAC, 50 - 60 Hz
  • AC Power Consumption (1/8 Power):
    • 100 VAC, 2.3 A
    • 120 VAC, 2.01 A
    • 230 VAC, 1.13 A
  • Material: 15 mm painted birch plywood
  • Finish: Black textured paint
  • Grille: Black powder coated 16 gauge steel
  • Dimensions (HxWxD): 20.1 x 23.4 x 29.9 inches with casters (510 mm x 595 mm x 761 mm with casters)
  • Weight (Net): 83 pounds (37.6 kg)

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