• Modular scalable column array system, for each size venue / application
  • 12" proribbon MHF drivers with up to 90% less distortion
  • Very high peak power handling for virtually infinite, dynamic headroom
  • All Neodymium drivers for excellent performancetoweight ratio
  • SIS prewired for very high damping and further reduced distortion
  • Shallow form factor and ACO™ color option for unobtrusive, "stealth" installation

Product description

The QR24 is a modular 2-way column loudspeaker to be used as vertical array system, for both permanent and (limited) portable applications.
It combines a perfectly natural, dynamic sound reproduction with superb intelligibility and throw, in even the acoustically most challenging environments.

The symmetrical acoustic design, in combination with the patented horizontal dispersion of the RBN HF drivers, offers a coherent horizontal pattern control with seamless coverage; This widens the “stereo sweet spot” significantly, for the off-axis positioned audience.

By using only 2 RBN drivers, the system’s active frontal radiation is close to 90%; The resulting sharply-controlled vertical dispersion offers a superb, SPL-independent, intelligibility over distance, without the necessity of DSP-based beam-shaping.

This controlled (cylindrical) projection can be extended down to the lower frequencies by enlarging the array length through adding extra QR/QM modules (extending the “near field”).

The passive filtering allows multiple modules to be combined on one amplifier channel, up to 3 units.

Each purpose-designed 12″ RBN driver has a peak power handling of 2.000W (200 msec), creating a virtually infinite system headroom of 4.000W from 1kHz up; Together with the high acoustical output, the system enables high-SPL sound-reinforcement performance.

The flat frequency response and the fast transient response of the RBN mid-high frequency transducers, in combination with the sharply controlled dispersion, brings a maximum “gain-before-feedback” up to directly in front of / under the system.

The QR24 is powered and controlled by the ALC amplified loudspeaker controller; Through the integrated processing and feedback, the ALC offers QR24-specific drive processing with optimal response and reliability and utmost user-friendliness.

The Signal Integrity Sensing™ pre-wiring ensures complete cable/connector compensation between the QR24 and ALC; This offers a 1:1, undistorted natural sound reproduction, regardless of cable length and amplifier impedance load (down to 2 ohms).

Dimensional drawing

Technical specifications

Frequency Response  
+/- 3 dB   74Hz - 20.000Hz
+/- 10 dB   53 Hz -
Nominal SPL (1W@1m)   109dB (200Hz – 10.000Hz)
Nominal Impedance   8 ohms
Recommended drive   Sentinel3 min.
Nominal SPL peak   137dB (Sentinel3 200Hz – 10.000Hz)
    141dB (Sentinel10 200Hz – 10.000Hz)
Dispersion H x V   80° x array length dep.


Physical specifications

System 2-way, full-range
Filtering   passive
Drivers LF   4x AND65/8 Neodymium 6.5”, vented
Driver HF   2x RBN1203 12” pro-ribbon driver
Cross-over frequency   1000Hz
Connectors   2x Speakon NL4 input / link
Physical dimensions   mm              inches
Height   660             26.0
Width   250               9.8
Depth   337                13.3
Weight (approx.)   22kg. (48lb)
Warranty   6 years limited


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