A Stradivarius is an analog computer that maps gestures into sounds by solving equations of motion. The reason why it's still preferred over an electronically synthesized cello is a question of good versus bad technology: the effective specifications of a Stradivarius are much better than those of a typical electronic synthesizer. But can we combine improvements in sensing, real-time computing, and mathematical modeling, in order to make a new instrument that can in a deep sense emulate and generalize a Stradivarius rather than in a crude way imitate it?

Yo-Yo Ma , Tod Machover, and Neil Gershenfeld collaborated to consider this question. Yo-Yo was interested in the prospect of an instrument that could give him new ways to communicate his musical intent to the listener while still retaining the mature sophistication of the combination of a great cello and cellist. For years Tod has been exploring the creative potential of smart musical instruments, moving beyond the traditional technological limitations on the level of description and division of labor among the composer, performer, instrument, and even the audience and the hall. And Neil Gershenfeld was struck by the realization that we're approaching a remarkable time when new technology can match the performance of nature at the level of description of a musical instrument, and so a descriptive model suddenly could become a playable model.

Working with Joe Chung and others, they built the "Hypercello". This is a musical instrument, like any other, that makes sounds in response to the player's actions. The interface looks almost like a traditional cello, but the RAAD body made by Dick Armin has been fitted with a range of new sensors developed for the project to measure the player's actions. These then go into a real-time computing environment that calibrates the data, parses it to find features, and implements high level rules for how gestures control electronically-produced sounds. It can be played like an ordinary cello, but can also do more. For example, bowing ponticello (near the bridge), can open up entirely new sonic pallettes rather than just sounding brighter. Or gestures can launch phrases or control algorithm parameters instead of just producing single notes. This paper describes some of the features of the sensing.

Tod's piece Begin Again Again ... was premiered by Yo-Yo at Tanglewood and has since been performed around the world.

Download an MPEG clip Yo-Yo playing the Hypercello

Download an MPEG clip of a rehersal