2x QSC AD-C4T-LP 4.5" Low Profile Ceiling Mount Loudspeaker

  • $374.00

The QSC AcousticDesign™ AD-C4T-LP is a 4.5" two-way low profile ceiling loudspeaker ideally suited for a wide variety of foreground and background sound reinforcement applications which utilize 70/100V or 16O bypass configurations. 

The AcousticDesign™ Series offers integrators a premium quality installed sound solution where performance, consistent coverage, and aesthetics are paramount. Specifically designed to maintain a consistent tonal characteristic across the entire family in ceiling, surface, and pendant applications, the AcousticDesign series allows integrators seamless transitions within blended installations. 

The AD-C4T features a high quality 4.5" weather treated paper cone woofer with a 1" voice coil and a .75" aluminum dome tweeter which is positioned on a DMT waveguide. 

DMT (Directivity Matched Transition™) is QSC’s design philosophy where the high frequency waveguide is matched to the natural conical behavior of the woofer at the crossover point. The result is a coherent transition between transducers with improved off-axis power response for consistent 150° conical DMT coverage. 

The accurate frequency response of the AD-C4T-LP is maintained even in 70/100V applications by use of a low-loss, lowsaturation 30-watt transformer with selectable taps, including 16O bypass, using a rotary selector located under the snap-fit magnetically attached powder coat steel grille. 

To retain lasting good looks, the rugged ABS baffle is further protected by using UV inhibitors that prevent discoloration and by a powder coated steel back can. The magnetic grille features a stick-on logo that can be removed blemish-free for installations where branding is not permitted. 

Installers will appreciate the 3x double stepped, long travel dog-ear blind mounting system, which captures from 0" - 2.25" of ceiling thickness. The conduit cover plate can be easily removed by losening the single captive Phillips screw allowing access to the locking 4-pole Euro-block connector which can accept up to four 18AWG pairs, eliminating the hassles of star topology wiring designs. 

Intrinsic Correction™ voicings that optimize performance and speed the install process are easily deployed via the Q-SYS Platforms, including CXD Series amplifiers, as part of a complete QSC systems solution. 

The AD-C4T-LP is available in QSC standard white (RAL 9010) and may be painted to match any decor.


  • Consistent tonal characteristics across the entire AcousticDesign family for surface, ceiling, and pendant applications
  • DMT (Directivity Matched Transition™) waveguide ensures smooth, uniform frequency response over the coverage area
  • Snap-fit magnetic grille
  • 3x double stepped, long travel dog-ear blind mount system
  • Intrinsic Correction™ voicings available via Q-SYS Platforms and CXD amplifiers
  • Low-saturation and low-loss 70/100V transformers with 16O bypass
  • Blemish-free removable logo
  • Removable conduit cover plate, also available as accessory for pre-install wiring
  • UL1480 and UL2043 certified


  • LF transducer: 114 mm [4.5 in] weather treated paper cone woofer
  • HF transducer : 19 mm [.75 in] aluminum dome tweeter
  • Effective frequency range: 1 70 Hz – 20 kHz
  • Rated noise power / voltage : 30 watts / 22 volts (rms)
  • Sensitivity [dB] : 87
  • Rated coverage (-6 dB) : 150° conical DMT
  • Directivity factor : 4.5
  • Directivity index [dB]: 6.5
  • Maximum continuous SPL [dB]: 102
  • Maximum peak SPL [dB]: 108
  • Nominal impedance [ohms] : 16
  • Recommended amplifier : 60 watts
  • Transformer taps / impedance : 16O (in bypass setting); 3.75W (70V); 7.5W (100V) Tap: 1333O; 7.5W (70V); 15W (100V) Tap: 667O; 15W (70V); 30W (100V) Tap: 333O; 30W (70V); N/A (100V) Tap: 167O
  • Input connector type : Euroblock connector with parallel output
  • Enclosure material : ABS baffle on powder coated steel back can
  • Grille material : Powder coated steel
  • Ingress protection : IP-34
  • Operating environment : Designed for indoor use
  • Operating temperature range : -20 to 50° C [-4 to 122° F]
  • Cutout dimension : Ø 245 mm [Ø 9.65 in]


(2) C-ring and tile rails
(2) Rail screws
(2) Euroblock connector
(1) Cut-out template
(1) Tether grille
(1) User's Manual