How ribbon loudspeakers work

How they work

Pierre Christin (December 2002): The ribbon is suspended between two magnets.The thin, narrow metallic ribbon is suspended within the magnetic field, a signal is applied to the metal ribbon. The signal in the ribbon causes it to be repelled and attracted by the magnets generating motion and thus sound. A ribbon tweeter is quick to respond to signal changes thanks to its low mass, lightweight nature. Suspended

Planar-magnetic drivers are typically used for high and middle frequency sounds. The ribbons are not very efficient at producing deep bass, so most planar-magnetic speaker designs mate a typical dynamic bass driver to the ribbon or ribbons used for the upper frequencies. Due the low mass of the ribbon, planar-magnetic speakers are able to react very quickly to transients and provide a great deal of detail similar in effect to electrostatic designs.

Chuck (November 2002): There seems to be some confusion on the Ribbon Loudspeaker forum. Many of the "ribbons" shown (the Carver being typical) are not ribbons at all. They are planar magnetic drivers, and as I understand it, the two uses Mylar. A true ribbon driver does not, using an aluminum ribbon (hence the name) instead of a Mylar diaphragm. IMHO, it is a mistake to confuse the two driver types.

True-ribbons have the magnets beside the ribbon, while the quasi-ribbons have the magnets in front of and/or behind the diaphragms. Thanks, Chuck

Magnepan web site (November 2002): Quasi ribbon / Planar-Magnetic Driver

This unique technology developed by Magnepan is the heart of Magneplanar speaker. The Quasi-Ribbon shown is basically the same driver used for the mid and low frequencies of the Magneplanar speaker with the infusion of a heavier gauge wire replacing the thin aluminum ribbon. Using a .0005" Mylar diaphram and a .001" ribbon this diapole, cabinetless design leaves the sound absolutely un coloured by box resonances.

The electronic properties of this design requires no transformer to compress the signal path and thus 'squeeze' the details tha xxxxxxx re kind to your amplifier and let your music free with an amazing imaging stage, and superb tonal accuracy. They require an amplifier with the ability to drive a 4 ohm load,

True Ribbon Driver

With its 360 degree radiating dipole design, the Ribbon Driver is found in our award winning MG 3.6/R and MG 20/R speakers

How does the Ribbon work

A tissue-thin foil ribbon is suspended in a magnetic field. This ribbon conducts a 'current sheet' that varies with the magnitude and frequency of the music to be reproduced. In essence, the magnetic field and current in the ribbon interact to produce a uniform force resulting in musical output, The unique way in which the ribbons are suspended and the geometric structure surrounding the ribbons contribute to the remarkable response time and the quality and precision of sound replication in an Apogee loudspeaker. Our transducers are specifically calibrated to perform smoothly and uniformly within a frequency range that covers the sound spectrum generated by musical instruments or heard by the human ear.