There are essentially three technologies used in invisible
speakers — the vibrating puck, constrained layer damping, and traditional
speaker units attached to a substrate.
Amina uses NXT's patented vibrating
puck technology to excellent effect. A small puck is adhered to a thin
substrate which produces highly accurate, enveloping output. The puck design,
however, has limited bandwidth, and only goes down to about 120 Hz — missing an
entire octave of bass. Amina recommends using an optional subwoofer (which does
not use a puck) to create full-range music.
We’ve developed the Live-Wall line of invisible speakers using a constrained layer damping system that excels in extension, accuracy,
and envelopment. It also has the lowest distortion measurements in the field. Constrained
layer damping flattens a traditional cone and tunes the system through a
sandwich of materials with varying densities and shapes.
Our bass extension and output is enviable, and our high frequency output extends past the range of human hearing.
Stealth Acoustics, Sonance, and several
other brands use traditional (non-patentable) speaker elements adhered in one
fashion or another to a substrate. While capable of producing a great deal of
output and good bass extension, these designs suffer from higher distortion and
limited dispersion. These negative traits are inherent in the design, and
create a soundscape overemphasizing some notes, while muffling others.