1 PC Sounderlink Pfofessional Speaker Planar HiFi AMT ribbon tweeter PA

A ribbon tweeter uses a very thin diaphragm (often of aluminum, or perhaps metalized plastic film) that supports a planar coil frequently made by deposition of aluminium vapor, suspended in a powerful magnetic field (typically provided by neodymium magnets) to reproduce high frequencies. The development of ribbon tweeters has more or less followed the development of ribbon microphones. The ribbon is of very lightweight material and so capable of very high acceleration and extended high frequency response. Ribbons have traditionally been incapable of high output (large magnet gaps leading to poor magnetic coupling is the main reason). But higher power versions of ribbon tweeters are becoming common in large-scale sound reinforcement line array systems, which can serve audiences of thousands. They are attractive in these applications since nearly all ribbon tweeters inherently exhibit useful directional properties, with very wide horizontal dispersion (coverage) and very tight vertical dispersion. These drivers can easily be stacked vertically, building a high frequency line array that produces high sound pressure levels much farther away from the speaker locations than do conventional tweeters.

Planar-magnetic tweeter

Some loudspeaker designers use a planar-magnetic tweeter, sometimes called a quasi-ribbon. Planar magnetic tweeters are generally less expensive than true ribbon tweeters, but are not precisely equivalent as a metal foil ribbon is lighter than the diaphragm in a planar magnetic tweeter and the magnetic structures are different. Usually a thin piece of PET film or plastic with a voice coil wire running numerous times vertically on the material is used. The magnet structure is less expensive than for ribbon tweeters.