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Classic Series

critically acclaimed acoustic suspension loudspeakers

Model 10S   

Model 10S

NSMT Model 15SE

Model 15SE




NSMT Model 75

Model 75


Clairvoyant Monitor
Clairvoyant Monitor


Acoustic Suspension Loudspeakers

Acoustic suspension (sealed box) loudspeakers, which are also known as infinite baffle loudspeakers, use cabinets that are sealed enclosures to shape the frequency response of transducers (drivers) with appropriate "parameters." In an acoustic suspension design loudspeaker the volume of air in the sealed cabinet is used to control the motion of the cone and to shape the driver's frequency response, particularly bass response.

Acoustic suspension loudspeaker design is based on mathematical modeling of the driver's performance characteristics and how these characteristics interact with the volume of air sealed in the loudspeaker cabinet. The development of acoustic suspension loudspeakers in the late 1950s is credited to the work of Edgar Villchur in 1954 that was put into commercial production by Villchur and his student Henry Klosss when they founded Acoustic Research loudspeaker company in Cambridge, Massachusetts, USA in the late 1950s.

Acoustic suspension loudspeaker design revolutionized loudspeaker manufacturing and allowed the stereo revolution to take off because, whereas before very large loudspeakers were needed to generate any kind of respectable bass response, acoustic suspension design provided a way to design and manufacture small inexpensive loudspeakers with good, linear bass response.

Although acoustic suspension loudspeakers are not very popular today (we are one of the few manufacturers still manufacturing them) as they were in their heyday of the late 1950s through the 1970s, they are gaining popularity again, in part, because of the increasing popularity of desktop music systems. This is because acoustic suspension loudspeakers that are the same size as ported loudspeakers will usually produce better and more accurate low bass response. They will have better transient response which will contribute to better imaging and better resolution of low level detail.

Why are ported loudspeakers more popular? Because they are more efficient and produce more voluminous bass. But, in general, they don't work well on desktops or bookshelves because usually the ports are on the rear of the speakers and that muddies-up the bass when they are placed near to rear walls. If you value accurate sound reproduction, everything else being equal, acoustic suspension loudspeakers have less distortion than ported loudspeakers.

Our extensive research leads us to conclude that, although it may not be obvious, transmission line loudspeakers have more in common with acoustic suspension loudspeakers, if only in terms of performance characteristics, than they do with ported loudspeakers. Like acoustic suspension loudspeakers, transmission line loudspeakers (one of the designs we prefer) have very linear extended bass response and excellent transient response. In fact, our approach to transmission line design is to treat it as a special case of acoustic suspension loudspeaker design.