the concept behind the ribbon speaker is rather straightforward. A thin strip of conducting foil (the ribbon) is suspended between the poles of powerful magnets. The ribbon is secured at the top and bottom and moves within the magnetic field as the amplifier’s signal stimulates the magnets, resulting in a pleasing, open sound.
The ribbon speaker was patented in 1923, but its popularity has been sporadic due in part to three critical impediments that Gilbert Briggs, the founder of the speaker company Wharfedale, identified more than 50 years ago. Briggs recognized that ribbons are unsuitable for reproducing bass frequencies, too expensive to manufacture because of the large magnets, and inherently delicate.
Today, Aerial, Burmester, Element, Tact Audio, VMPS, and other companies are producing hybrid speakers that include ribbons for the highest frequencies and leave the lower notes to conventional drivers. A factor behind the current ribbon revival is the increasing popularity of home theaters. Although ribbons are available in cabinet-style speakers, consumers are insisting on speakers with profiles as slim as plasmas, LCDs, and other flat-panel televisions. Also, in a home theater, an array of five or more ribbons produces an open surround-sound experience that is far more convincing than traditional tweeters.
The Danish company Dali uses a proprietary tweeter module in its Euphonia line (MS4 and MS5 floor-standing speakers, CS4 center, and RS3 surrounds). Inside a separate element, a 29mm soft dome tweeter encapsulates a 10-by-55mm ribbon that handles the crucial upper frequencies. Cone-type drive units reproduce the bass.
A new company from Switzerland called 440Hz produces a ribbon tweeter that fits into slim, elegant columns—a design that exploits a ribbon’s thinness. The Largo incorporates nine ribbon columns and 16 cone midrange drivers in a 6-foot-tall tower. The panel, however, measures just 6 inches wide and just over 41⁄2 inches deep. An external subwoofer handles the base. The company is focusing on home theater applications, claiming that the speakers’ thin and shallow dimensions make them the most room friendly.
Piega, another Swiss brand, uses a small ribbon tweeter throughout its 14 models, ranging from bookshelves to floor standers. The boat-tailed, polished aluminum cabinets are meant to mirror the metallic constituent of a ribbon driver, and a metal surface, rather than wood, usually serves as a better complement to plasma screens, which tend to have metal frames.
Meadow Song Labs, located outside of Toronto, is truly ambitious. The Mont Blanc, with its 40-inch ribbon mounted in a transparent acrylic baffle, covers all frequencies above 250Hz, thus coming close to functioning as a full-range ribbon. The company also offers a smaller system, the Jaguar, with the midband served by a 7-by-2-inch ribbon.
It is unlikely that this flood of new ribbons will redress the balance and restore the technology to its place atop the speaker tree. Conventional round tweeters offer an alternative that is too inexpensive, robust, and reliable for that to happen. But for those who crave a little extra airiness—a sound quality that falls between that of typical tweeters and electrostatics—ribbons are a grand-prize winner.
440Hz, http://www.440hz.ch; Dali, http://www.dali.dk
Meadow Song Labs, 905.764.7812
Piega, http://www.piega.ch
