Applications range from stand- or truss mounted single-unit mobile PA system, up to multiple-module flown array in reverberant halls or high ceiling theatres. But also as high power side-fill stage monitoring the QR36 offers new solutions, or as single-column main PA system in low-ceiling applications, where a J-curved line-array will not give satisfactory throw/dispersion results.The QR36 is a two-way passive-filtered modular line-source column. With a length of 1m (39"), the QR36 consists of 6x 6.5" woofers in frontal bass reflex-loading and two units of Alcons' RBN1801 18" pro-ribbon transducers with patented "Real-90" horizontal dispersion. The frequency response is 74Hz - 20kHz.(+/-3dB), with a lowest usable frequency of 53Hz (-10dB). Power handling is 780W RMS, bringing 129dB continuous output, while the 6000W peak power handling from 1kHz up, offers a 150dB "virtually infinite headroom", say the company.
As an "array of line-sources", a QR system acts as true cylindrical radiator, offering a 3dB SPL drop-off per doubling of distance. This brings significant advantages in SPL coverage and (intelligibility) throw, from a relatively simple system. When used in multiples, the QR's form a continuous line-source, extending the "near field" of the system over longer distance and lower frequencies.
The specific spacing of the sources (within half of wavelength) and the unprecedented frontal radiation of more than 92% make the QR36 compliant with the two most important line-array criteria, say Alcons. The result is a large main lobe without any significant spikes above and below the array, preventing ceiling reflections and offering unusually high gain-before-feedback.
(Lee Baldock)
