Wisdom Audio has a patent pending on a loudspeaker motor design that it believes offers many advantages compared with traditional moving coil designs. Wisdom Audio also presented a paper (No. 7847) on October 9 during the recent 127th Audio Engineering Society (AES) convention in New York on this new motor design.
According to David Graebener, Wisdom Audio executive vice president, among the advantages of this new motor design are higher output and efficiency, lower distortion, much lower power compression, and significantly higher reliability.
“The use of state-of-the-art FEA programs, along with incorporating some of the most advanced materials currently available, has made this approach far more effective than any of the previous designs that share aspects of this technology,” he explained.
The Motor Design
When applied to woofers, according to Graebener, this motor design has the potential for one driver to have the output of two or three moving coil drivers of the same diameter using the same enclosure size. The same is true when applied to midrange and midrange compression drivers.
When applied to dome tweeters, the goal is much higher power handling and an operating bandwidth that is a full octave lower than the best moving coil domes available anywhere. This would allow for creation of two-way designs with improved imaging and spatiality.
How It was Developed
Wisdom Audio has worked in conjunction with Dr. Marshall Buck of Psychotechnology Inc. and Patrick Turnmire of Red Rock Acoustics, in developing this highly advanced loudspeaker motor design.
Dr. Buck found that the induction drive technology, using a transformer coupling in the motor, allows additional design freedom that can be exploited in a variety of innovative ways. The elimination of moving lead wires increases reliability, and the motor strength can be substantially increased. Non-linear distortions can be vanishingly low. Dr. Buck and Turnmire developed accurate simulations of the new designs to facilitate optimization, leading to several working prototypes, the test results of which have been very promising.
The Licensing Opportunity
Wisdom Audio is developing expressions of this technology for future use in custom installed residential products targeted at the highest level of performance possible. Additionally, Wisdom is also creating a program whereby other loudspeaker companies can license this technology for professional and commercial audio applications, where this new motor technology will provide a wide range of unique benefits.
“It is our belief that truly advanced technologies like this are essential to the continued success and evolution of our unique approach to high performance loudspeaker manufacturing and associated marketing effort,” Wisdom Audio president, Mark Glazier, stated. “This belief is manifested in Wisdom Audio’s creation of the most sophisticated planar magnetic transducers currently available, all of which have been designed and are produced in Wisdom’s facility in Carson City, Nevada.”