DDS stands for Digital Directivity Synthesis - an advanced array control optimizationconcept. DDS is based on a specially adapted "constrained weighted least-squares" optimization algorithm. Starting from a desired direct SPL distribution in a hall or space, the optimum output filter for each array channel is calculated. In other words, the desired 'illumination' of the hall or space is 'mapped back' to the array, instead of mapping the arrayresponse to the hall, as would be done with a conventional loudspeaker array.
Using DDS technology, any desired two-dimensional radiation pattern can be synthesized from the IntelliDisc-DS90. This, the company says, allows users to 'mould' both the vertical and horizontal dispersion of the array to perfectly fit the audience area; whilst at the same time avoiding unwanted reflections. The result is an array which can offer a high ratio of direct sound to reverberant sound, which is critical for achieving high levels of speech intelligibility, in the most difficult of acoustic environments.
Duran Audio says this has proven to be a versatile and effective solution for vocal reinforcement within reverberant venues, offering excellent speech intelligibility even in demanding acoustic conditions. The IntelliDisc-DS90 is capable of providing a constant SPL over a distance of up to 30m, although a substantial extension of this range can be achieved in less demanding acoustical conditions.
The IntelliDisc-DS90 is equipped with two 32-bit floating point DSPs which handle the demanding mathematical calculations. In addition to this, the DSPs offers a wealth of useful audio processing features including volume control, parametric EQ and delay. The 41 custom designed, 4" loudspeakers are driven by a 32-channel class-D amplifier, power for which is provided by two sophisticated switched mode power supplies, all of which combine to ensure years of reliable operation, say the company.
An extensive set of surveillance functions have also been implemented to meet the stringent demands of typical VA applications. The unit can be controlled using Duran Audio's proprietary WinControl software, which offers user-friendly control of the beam steering parameters, audio processing and surveillance features.
(Lee Baldock)
