On March 11, 2010, University of Hartford B.S.E.E. graduate and former Bose engineer Dennis Gagne joined Hartford AES and Hartford ASA for a lecture on "Lumped, Linear Modeling of Direct Radiator Loudspeakers."
Gagne began by explaining that we can model characteristics of traditional, moving-coil speakers in all three domains - electrical, mechanical, and acoustical - using an electrical circuit model. He continued by investigating how each component in the model represents a parameter in the speaker, such as a series resistor to model the DC impedance of the voice coil and a transformer with a turns ratio proportional to the area of the speaker cone. Every variable was addressed, including the losses related to the stiffness of the enclosure and the effect of sound radiated from the rear of the box.
Dennis then showed how this model can be analyzed using LEAP 5 to generate impedance and frequency response graphs. In his provided list of references, Dennis suggested alternative programs for analysis
Gagne ended with a discussion of modern loudspeaker materials, explaining practical differences in the performance of paper, polypropylene, and aluminum cones and underlining recent advancements in ribbon transducer design.
This event was co-sponsored by the University of Hartford Acoustical Society of America Student Chapter. For more information about Hartford Acoustics, visit http://uhaweb.hartford.edu/celmer/index.htm
