Specifications

The third and final antecedent to consider is the ribbon: a
distinctly different sort of transducer, but one that is similar (in
principle, at least) to the single-ended planar magnetic. The
ribbon’s primary distinction is that its “diaphragm” and “voice
element” are one and the same.
A ribbon driver is based on a long, narrow strip of conductive
material; in practice, thus far, all true ribbons have used a strip of
very thin corrugated aluminum for this purpose. The two ends of
this strip are electrically connected to the amplifier’s output, and
are physically anchored such that the strip is suspended within a
stationary magnetic field--with said magnets positioned at the
edges of the strip.
PERMANENT MAGNET
PERMANENT MAGNET
ALUMINUM
RIBBON
ELEMENT
N
S
_
+
TO AMPLIFIER
[LEADS CONNECTED TO
TOP AND BOTTOM OF
RIBBON ELEMENT]
RIBBON DRIVER
[TOP VIEW CROSS-SECTION]
The operating principle is straightforward from there: the
amplifier’s output passes directly through the aluminum strip--
which, because it is suspended within a permanent magnetic field,
moves back and forth in synchronization with the signal,
producing sound.
Ribbon
Loudspeakers
13