QSC AD-C81Tw-WH AcousticDesign 8-Inch Ceiling Mount Subwoofer

Built to extend low-frequency audio systems, the AD-C81Tw ceiling-mount subwoofer system perfectly complements any ceiling- or surface-mount speakers from QSC’s AD Series.

QSC AD-C81Tw-WH Features

• Ceiling-mountable installed subwoofer
• Can also be installed on other flat surfaces
• Paintable white finish allows for discrete integration into your space
• Adds power to your background or atmospheric audio
• 8-inch polypropylene cone woofer
• Large port area for extended low-frequency performance
• Defeatable passive 120 Hz low-pass filter with impedance compensation
• 100W continuous power handling, 400W peak
• 70/100V multitap transformer with 8 ohm bypass
• C-ring and tile rails included
• Side cable entry

• AD-C81Tw-WH 8-Inch Ceiling Mount Subwoofer1
• C-ring and tile rails1
• Round grille (white, paintable)1
• Paint mask1
• Connector assembly1

• ConfigurationCeiling subwoofer, ported
• Low-frequency Transducer8-inch (20 cm) weather resistant, polypropylene cone woofer, rubber surround
• Frequency Range [1]
  • Frequency Response (-6 dB): 39 Hz to 184 Hz
  • Useable Frequency Range (-10 dB): 28 Hz to 208 Hz
• Filter120 Hz low pass, passive, bypassable
• Maximum Output [2]
  • Calculated Peak Output: 118 dB SPL
  • Calculated Continuous Output: 112 dB SPL
• Nominal Impedance8 ohms switchable
• Power Rating
  • Continuous power handling[3]: 100W (100 hours IEC)
  • Recommended amplifier power (loudspeakerprogram" power): 200W
• Sensitivity92 dB, 2.83 V, 1 m, free space (4 pi)
• TRANSFORMERS
  • Type: Custom low distortion laminated core, wide bandwidth design
  • Taps (switch selected)
    • 70V: 60, 30, 15, 7.5W; 8Ω
    • 100V: 60, 30, 15W; 8Ω
  • Environmental: Exceeds Mil Spec 810 for humidity, salt spray and dust; IEC 60529 IP-X3 splash rating
  • Agency Rating: Listed UL1480, UL2043 safe for use in air handling spaces; Transformer is Listed UL1876; Compliant BS/EN 60849 safety standards
• ENCLOSURE
  • Material: Injection molded, high impact polystyrene baffle on a steel enclosure
  • Finish: White (paintable)
  • Grille: Painted aluminum
  • Connectors: Ceramic block or 4-pin Euro terminals in fire protective sub-chamber
  • Mounting Hardware: Rails and C-ring for ceiling tile installation
  • Weight
    • Net: 20 lbs (9.1 kg)
    • Shipping: 28 lbs (12.7 kg)
    • Available Accessories: ADC-MRS Mud ring bracket • ADC-NCS New construction bracket
• Notes
  • [1] All frequency ranges specified refer to measured free field response
  • [2] Calculated SPL at 1 m, (free space, 4 pi), speaker operating at rated continuous power with pink noise within specified frequency range
  • [3] Maximum input power tested in accordance with IEC 268-5 recommendations, 50 Hz to 20 kHz band limiting, 6 dB signal crest factor

Built for Powerful Performance

Offering 92 dB SPL sensitivity, the AD-C81Tw is rated for 100W continuous power handling and can stand up to 400W peaks. Its 8" woofer features a polypropylene cone for better durability in humid environments.

The driver features a synthetic rubber surround and works optimally with the large port to extend frequencies below 40 Hz.

A built-in passive low-pass filter is set at 120 Hz and is defeatable from the front baffle to allow the use of outboard crossovers. Additionally, the AD-C81Tw is equipped with a 70/100 V transformer with multiple taps and an 8 ohm bypass.

Designed for Durability

Every component of the AD-C81Tw has been designed for quality, durability, and performance. Its baffle and mounting tabs are molded from high-impact polystyrene.

The rear enclosure is heavy gauge, powder-coated steel, while the aluminum grille is backed with an acoustically transparent white cloth. The input cup is mounted on the enclosure’s side to reduce the amount of vertical clearance required for installation, and the cup’s cover features a conduit attachment point plus an additional knockout for daisy-chain wiring. Input signal connection is made with a ceramic screw terminal that is resistant to high temperatures.

Included Components

The AD-C81Tw comes with C-rings and tile rails for installation.

More about QSC's AcousticDesign Installation Speakers

Easy installation, flexible mounting options, and rugged, high-weather resistance are just three of the features that set QSC’s AcousticDesign™ series apart.

These premium loudspeakers are designed to give contractors and integrators versatile, reliable solutions for permanent sound installations.

Unified by premium audio quality and consistent tonal characteristics this series is comprised of ceiling, surface, and pendant alternatives ideal for environments where you need the perfect combination of performance, coverage, and aesthetic appeal.