Alcons Audio has introduced the QR24, a modular two-way column loudspeaker to be used as vertical array system for permanent and (limited) portable applications.
Due to its modularity, throw and low-frequency directivity (close-field) can be increased by extending the array length, while multiple individual mid-high frequency lobes can be made, by using QM low/mid fill columns.
The QR24 measures 66cm/26-inch tall in length, and is fitted with four 6.5-inch woofers and two purpose-built 12-inch pro-ribbon drivers. The RBN03 pro-ribbon platform was developed for this system, accommodating a co-axial driver arrangement with the LMF transducers, which are, at the same time, actively cooling the RBN drivers for further power compression reduction. Each purpose-designed 12-inch RBN driver has a peak power handling of 2kW (200ms), creating a virtually infinite system headroom of 4kW from 1kHz up.
By using only two RBN drivers, the system’s active frontal radiation is close to 90 per cent; The resulting sharply-controlled vertical dispersion offers SPL-independent, intelligibility over distance, without the necessity of DSP-based beam-shaping.
The symmetrical acoustic design, in combination with patented horizontal dispersion of the RBN HF drivers, offers a coherent horizontal pattern control with seamless coverage – this widens the stereo sweet spot for off-axis audience. The projection pattern in the horizontal/non-coupling plane is 80° (-6dB) and in the vertical/coupling plane, it is 6° (single column).
The system frequency response is flat (-3dB ) from 74Hz to 20kHz, to easily match a accompanying subwoofer system, catering for a relatively simple bi-amplified, three-way system. 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 on/under the system. Passive filtering allows up to three QR24 modules to be combined on one amplifier channel, with an array length of 2m/7ft.
The QR24 is powered and controlled by the Sentinel amplified loudspeaker controller. Through the integrated processing and feedback, the Sentinel offers QR24-specific drive processing with optimal response and reliability, and 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 (system damping factor >10.000 down to 2Ω).
