CITATION FOR GABRIEL WEINREICH
…for contributions to violin and piano acoustics.

MIAMI, FLORIDA - 12 NOVEMBER 2008

If anyone ever deserved the title “Renaissance man” it is Gabriel Weinreich. Physicist, theologian, linguist, philosopher, musician, humanitarian, inventor, and acoustics researcher: Gabi has distinguished himself in so many ways. He has published books on the theory of condensed matter (1965), thermodynamics (1968) and extended vector mathematics (1998), as well as extensive notes that have guided physics instruction at Michigan and elsewhere. However, it is his contributions to musical acoustics for which we honor him today.

Gabi was born in Vilna, Poland (now Vilnius, the capital of Lithuania) in 1928. His father, Max Weinreich, was a linguistic scholar of note and a founder of the YIVO Institute of Jewish Social Science. When the Second World War began, Gabi’s family came, in serial fashion, to New York City–Gabi and his mother escaping in 1940 via train across Siberia. Gabi studied physics at Columbia University and received a Ph.D. in 1953 for a thesis on atomic physics directed by the legendary Nobel laureate, I. I. Rabi. He subsequently worked on fundamental properties of semiconductors, first at Bell Labs, then, starting in 1960, at the University of Michigan. Perhaps most significant among this early work was the theory and (subsequently) the observation of the acoustoelectric effect, where an ultrasonic wave in a semiconductor gives rise to a direct electrical current.

In 1977 he turned his attention to the acoustics of musical instruments, mainly the piano and bowed strings. What a fortunate day it was for acoustics when he became interested in the problem of super radiance in coupled piano strings! He studied all phases of the physical elements: string excitation, string vibration, coupling, and radiation. Later he turned his attention to violins, and his creativity has brought renewed life to this longstanding field of study.

Gabi brought his special style to acoustics—a combination of theory and experiment that imaginatively imports ideas and techniques from one area of physics into another, a willingness to attack traditional problems afresh by returning to first principles, and the ability to present ideas with incisive wit and charm so that information is not only informative but is also entertaining. His papers at meetings of the Acoustical Society of America (ASA) are classics, both for the scholarly content and the passion with which he delivers them.

His seminal papers on violin acoustics have steered the way we think about the subject and helped to guide the research of others. One such paper in the Journal of the Acoustical Society of America (JASA) was “Sound hole sum rule and the dipole moment of the violin” (1977) which defined radiativity and showed how a vibrating hollow shell with a sound hole would radiate as a dipole at low frequencies. Another was his paper on “Directional tone color” (1997) which formed the basis of his patented invention of the directional tone color (DTC) loudspeaker for accurate reproduction of the sounds of violins and other musical instruments. His Klopsteg Memorial Lecture to the American Association of Physics Teachers (1992) on “What science knows about violins—and what it does not know” was published in the American Journal of Physics. His Scientific American cover story on “The Coupled Motion of Piano Strings” (1979), based on his earlier JASA paper (1977), is one of the most widely quoted articles on musical acoustics. It explained the initial sound and the decaying sound of a piano in terms of the horizontal and vertical vibrations of a single string and the coupled vibrations of two or three strings. Most of the research on the piano was done in his own living room before he had developed an acoustics laboratory at the University of Michigan.

Gabi’s fame is truly international. His linguistic accomplishments include fluency in French, German, and Yiddish. One of his hobbies is translation of scripture from Hebrew to English (he is a priest in the Episcopal Church). He has collaborated extensively with French scientists at Institut de Recherche et Coordination Acoustique/Musique (IRCAM) and Laboratoire d’Acoustique Musique in Paris. With René Caussé, he created the electronic violin bow, which excites the violin string via the Lorentz force on a current in a magnetic field. The new science entered because the current was computed through feedback from the string motion itself in such a way as to simulate the stick-slip motion of the bow. After months of work Gabi and René succeeded in achieving the rotating-kink Helmholtzian motion, which led to new insight on the stability of this motion. With Xavier Boutillon, Gabi invented a new way to measure mechanical admittance and applied it to the bridge of a violin. As a result of this and similar work, Gabi received the Foreign Medal of the French Acoustical Society in 1992, and was awarded the first Carleen Hutchins Gold Medal for Lifetime Achievement in Musical Acoustics in 2002.

It is typical of Gabi’s style that while working on musical acoustical problems, he should take a little break and invent some pure mathematics. Everyone “knows” that a vector is an arrow–characterized by length and direction, but in his book, Geometrical Vectors , Gabi showed that in order to make a logically consistent vector calculus, arrows need to be supplemented with other beasts, which he called “sheaves,” “stacks,” and “thumbtacks.”

In spite of his many accomplishments, Gabi retains his modesty and remains a friend of all of us in the musical acoustics community. MacArthur Foundation awardee violin maker Joseph Curtin wrote in The Strad (2000) “Weinreich is one of those joyfully articulate people who speak in publishable sentences. He can carry an idea, in the face of digression and interruption, with the agility of a star football player carrying a ball down the field.” He is never too busy to use his remarkable physical insight to help a colleague with a difficult problem. He is always there when we need him.

THOMAS D. ROSSING

WILLIAM M. HARTMANN