The result is maximum utilization of the energy from the magnetic structure and maximum efficiency.
Finally, the large diameter coil yields a stronger moving structure since the force applied to the coil is transferred to the cone over a larger area. There virtually is no loudspeaker market for which the D130 did not find application.
It incorporated a 4" flat wire voice coil attached to a light, curvilinear cone with a 4" aluminum diaphragm instead of a standard dust cap to extend high frequency response.
The coil was immersed in one of the strongest permanent magnetic fields yet developed for a loudspeaker.
In the 1950's through the 1960's, it was the loudspeaker that defined the home hi-fi phenomenon.
It was used in more component hi-fi systems of that era than any other speaker. Lansing Sound's first commercial systems for the movie industry.
It resulted in a driver with outstanding sensitivity, range and dynamic response.
The 4" flat wire coil was the single most innovative feature of this design.
Illustrated at left is a letter written by James Lansing to Arnold Engineering, then the major supplier of Alnico V used in permanent magnets.
It is a fascinating insight into the early days of James B Lansing Sound.