Specifications

Also, when a ribbon is operated at frequencies approaching the
element’s own resonant frequency (which is naturally quite low,
due to its high compliance), the ribbon element stretches and
“bows” to a point where it is no longer within the magnetic gap.
To get around either of these problems means to move the
permanent magnet structure from the edges of the element to one
entire side of the element, and/or to bond the element to a “host”
diaphragm, such as a sheet of Mylar, and to clamp that diaphragm
around its perimeter. In either case the driver is no longer a
ribbon; it is, in fact, a planar magnetic. To date, no one has
succeeded in creating a full range ribbon loudspeaker.
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