Meridian's Digital In-wall

Long known as a leader in digital audio and video technologies, Meridian Audio Limited has taken digital signal processing (DSP) into a new realm with the introduction of the DSP420, an "architectural" in-wall speaker that applies the British manufacturer's expertise to the problems of built-in designs.

The "digital loudspeaker" concept is a natural for the custom installation market, according to company chairman and chief designer Bob Stuart. "There probably is no environment with a higher payoff for our expertise in this field than that of the in-wall speaker," he says. "The problems facing any built-in design, both acoustical and practical, are formidable indeed; using DSP we can surmount them with demonstrably more success than a more conventional approach."

The Meridian DSP420 is based on a non-resonant, fully enclosed in-wall aluminum “back-box” and baffle said to completely control driver behavior and eliminate structural vibrations as a source of coloration. The enclosure also is fully shielded, permitting installation in close proximity to video displays. The driver complement consists of dual 5" bass/midrange units and a single Meridian 1" aluminum-dome tweeter—the configuration used in the freestanding Meridian DSP33. Like that model, the DSP420 utilizes two channels of built-in active-speaker amplification: 85 watts for the woofers and 65 watts to the tweeter in a biamplified, active-speaker configuration that completely sidesteps the hurdles of conventional, passive crossover/driver systems – "among the biggest limiting factors of traditional-speaker performance," according to Stuart.

Self-powered speakers are not revolutionary, but Meridian takes the concept to a new level by incorporating digital-to-analog conversion within each speaker module – in essence, combining the functions of speaker, power amp, pre-amp, and DAC in one compact product. Each DSP420 receives its channel’s digital signal from a Meridian preamp or controller, accepting bitstreams of up to 96/24, including the company’s proprietary MHR enhanced-resolution format. An on-board Motorola DSP engine lets the DSP420 perform linear-phase crossover, for "a precision of driver integration no conventional speaker can approach, and small-scale, driver-correction equalization that yields near-perfect accuracy." DSP is also achieves "perfect time-domain driver alignment, for solid, dimensional imaging and stable timbral accuracy." The technique can be exploited to “push back” the walls, letting a Meridian Digital Theater user experience a larger virtual-acoustical space.

Each DSP420 utilizes a full-system master-volume control implemented with 48-bit precision, transparent DSP tone-control functionality, and Meridian’s proprietary active bass extension technology – a "psychoacoustically correct, level-aware frequency contouring to produce dramatically deeper, more dynamic bass at typical real-world volume settings than would otherwise be conceivable from a speaker of its size, all the while preventing any possibility of bass distortion or woofer bottoming at higher levels. "

Suggested retail price for the DSP420 is $5,000/pair, available at Meridian dealers as of late January.

X