Laser-Accurate technology revolutionizes the very concept of the microphone, trading mechanical parts movement for the patented and incredibly precise measurement by a laser of the movement of particulates suspended in air Proof-of-concept will be demonstrated by Laser-Accurate inventor and digital audio pioneer David Schwartz at the Schwartz Engineering & Design booth on the AES show floor
New York, New York (September 21, 2009) –- There have been several key milestones in the evolution of the microphone, from the development of the basic transducer in the 19th century, to the introduction of the condenser microphone in the 1920s, followed by FET microphones in the 1960s and the more recent multichannel microphones used for surround audio applications. The next step in this evolutionary procession will be introduced at the 127th Audio Engineering Society Show, Oct. 9-12, 2009, at the Javits Center in New York City. Laser-AccurateA® technology, from Schwartz Engineering & Design (SED), the leader in optical microphone design, represents a revolution in microphone technology: instead of the conventional diaphragm whose resonance creates electrical impulses against a coil or a back plate, Laser-Accurate technology uses a laminar stream of air in a chamber in which microscopic particles are suspended. When excited by changes in air pressure, the movement of these particles is detected by a laser beam that continuously passes through the chamber aimed at a photoelectric cell opposite the laser source. As a result, Laser-Accurate will produce the most accurate and precise transduction of any sound. It is, in essence, the Perfect Microphone, capturing sound unadulterated by the mechanical motion of the diaphragm and the inevitable time lags caused by that movement. All that is eliminated by Laser-Accurate’s design. All you get, for the first time ever, is pure sound.
Conventional microphone design has numerous inherent idiosyncrasies: the speed with which a traditional diaphragm can react is innately limited by its physical size and shape, and the variety of those mechanical elements inevitably adds tonal coloration – distortion — to the sound it’s recording. In the design of Laser-Accurate, the diaphragm or plate is replaced with microscopic particles dispersed in a gas-filled chamber in which the laminar flow of the gas is constant. Detection of the displacement of the airstream and particles by a laser and optical receiver creates a completely non-intrusive method by which to measure the movement of air. This arrangement means no significant mass stands between the source of the sound and the transduction of it to a recording media.
An entire professional audio culture has been built upon the colorations that various microphones bring to music. Laser-Accurate does not threaten that culture in any way; rather, in addition to providing an absolutely pristine transduction process, it also acts as the ultimate standard by which all microphones can be evaluated. David Schwartz, developer of Laser-Accurate technology and a holder of six critical digital audio patents, including one that is the basis for the MP3 file format, is himself an audiophile. “The color that certain microphones bring can be fantastic,”? he says. “The problem is, you can’t have all of them, all of the time, meaning that all music recording is a compromise of some sort. With Laser-Accurate technology, all the tonal processing would take place after the sound is converted to a voltage, not during the act of recording it.”? A pristine signal offers a new world of possibilities, including the potential to create “plug-in”?-type chip-based processors that mimic the characteristics of classic microphones and pre-amps, much as modeling guitar amplifiers routinely do now.
Laser-Accurate technology will be demonstrated throughout the four days of the AES Show. It will provide a completely new tool for microphone developers to create the next generation of how we capture music and sound.