In 1991, the hyperinstrument team designed a special hypercello for Yo-Yo Ma. Begin Again Again... is the "Inferno" of the trilogy. It was composed for Yo-Yo Ma, who premiered the piece at the Tanglewood Festival in August 1991. The work is scored for solo hypercello, with the performer controlling an array of sound producing and transforming devices. It is about twenty-five minutes long and has ten uninterrupted sections, all distinct in character, which are grouped into two large-scale movements. The first movement is increasingly agitated, energetic, and dramatic; the second is more lyrical, calm and introverted. The title of the piece refers to its musical form and expressive content. Begin Again Again... is a set of variations in which the same melodies and harmonies are returned to over the course of the work, each time expanded and elaborated in new and unexpected ways. Similar to the Sarabande of Bach's Suite No. 2 for Solo Cello (from which the initial ideas for the piece grew), the hypercello line revolves cyclically around the middle D of the instrument, trying constantly to ascend but being ever pulled down to low pedal tones. The hypercello eventually breaks free from the weight of repetition, but not before considerable struggle. As Machover has written: "This serves as a metaphor for change in our lives - of breaking with the past while retaining what is dearest to us; of opening up doors to unknown possibilities; and finally, of renewed hope and affirmation."
The hypercello allows the cellist to control an extensive array of sounds through performance nuance. Special techniques (wrist measurements, bow pressure and position sensors, left hand fingering position indicators, direct sound analysis and processing, etc.) enable the computer to measure, evaluate, and respond to as many aspects of the performance as possible. This response is used in different ways at different moments of the piece: at times the cellist's playing controls electronic transformations of his own sound; at other times the interrelationship is more indirect and mysterious. The entire sound world is conceived as an extension of the soloist--not as a dichotomy, but as a new kind of instrument.
"The hypercello...serves as the input device to a stack of machines that process the data created by a performer and generate a variety of different types of responses. As the cellist plays the cello, sensors [developed by Neil Gershenfeld] tell one bank of custom electronics the angle the cellist's bow-hand wrist forms, where the bow is on the cello's strings, how much pressure the cellist is placing on the bow, and where the cellist is fingering the strings on the fingerboard. The special circuitry hooked up to the cellist's sensors then translate that analog data into digital information and transmit the results to the system's main computer, which can then transfer that data as MIDI information. At the same time, the electronic signal of the tune actually being played gets fed directly into a synthesizer, which can either manipulate the data or pass it through as a (sort of) conventional cello sound.
"To execute musical functions, Machover and Joe Chung developed a set of software tools to control the flow of information from a performer to his machines. The bow sets up vibrations on the cello's strings - just as in ordinary versions of the instrument - but at the same time it can act as a conductor's baton, with the position of the tip of the bow, the length of the bow drawn across a string per second, the pressure on the bow all controlling musical parameters: the number of musical lines called up from the computer, the timbre of the pitches being played, the attack, and so on. Machover's interest in timbre in particular led to the development of a technique designed to permit the performer to add the pure cello sound coming off the strings to sampled or synthesized timbres stored as MIDI data within the computer, allowing the performer to decide precisely how much of his own playing he wanted to hear. The computer can then generate an accompaniment to the cellist's solo, one whose pace and rhythm would be controlled by the performer. As it executes each of these functions, the main computer processes the data it receives, modifying or even creating sounds, depending on the instructions contained within its software.
"The software here is both part of the instrument, an element of the system that generates a sound, and part of the score, the list of the composer's choices of what sounds should be heard when. The system as a whole thus acts as both an instrument to be played by the performer and as an orchestra responding to the performer's commands, as if the cellist were a conductor as well.
"Begin Again Again... is, like Stockhausen's Kontakte, at once an expression of musical thought and feeling and a report on the current state of the art of the technology of making music."
In fact, Begin Again Again... is, among other things, about the idea of creating a hyperinstrument. It starts out with the performer exerting careful control over the electronic extensions, each bow change, each accent chosen to elicit a specific response. Gradually, however, the computer part starts to develop on its own - as if a Pandora's Box had been opened - becoming denser and more complex than a single human could control. After an explosion at the work's climax, the piece "starts again," tentatively at first, but soon establishing a gentle, balanced dialogue between performer and computer. At the end of Begin Again Again..., a hyperstring instrument has emerged, ready to continue the musical journey of the trilogy, drawing less and less attention to itself.