Guarneri Quartet cellist David Soyer, 87

The longtime Guarneri Quartet cellist David Soyer, 87, died late Thursday in his New York City home after an extended illness.

Mr. Soyer, born in Philadelphia, is credited with having a profound influence on American cello performance, thanks to his faculty position with the Curtis Institute of Music since 1968 as well as teaching affiliations with the Manhattan and Juilliard Schools.

Though chiefly based in New York, he was a near-constant hometown presence thanks to the Philadelphia Chamber Music Society, which presented him in 36 concerts over 23 years - 17 with the Guarneri and 19 as a guest artist with other musicians. Most recently, he was heard in the final Philadelphia performance by the now-disbanded Guarneri, playing Schubert's Quintet in C in May 2009.

"We tried to involve him as much as possible," said Anthony Checchia, founder of the Chamber Music Society. "I always loved his playing, artistry, and musicianship. For me, he was the consummate artist."

Heart trouble limited Mr. Soyer's mobility in recent years - just going on and offstage left him winded - but he maintained a strong standard of performance. His May Guarneri performance was considered as fine as any he ever gave. At the Marlboro (Vt.) Festival, where he had taught since 1961, he played two concerts last summer. Until two weeks ago, with the aid of oxygen he taught as many as 15 students a week.

Having begun playing at 11, Mr. Soyer studied with cellists who are now legends - Emmanuel Feuermann and Pablo Casals. He made his debut as a soloist with the Philadelphia Orchestra in 1942, before he was 20, and freelanced extensively in New York, collaborating with the Budapest String Quartet and playing under Arturo Toscanini in the NBC Symphony.

Those influences followed him to the end. He often passed on the simplicity of Feuermann's advice on note-to-note transitions: "Slide till you hear the note - and stop." On the night of his death, a friend said, he asked to hear the Schumann Piano Trio (Op. 63) as played by Casals.

Though involved in a number of chamber-music groups, including the Bach Aria Group, the Guilet String Quartet, and the Marlboro Trio, Mr. Soyer was most recognized for his years with the Guarneri, from its 1964 founding to his 2002 retirement, after which he was replaced by former student Peter Wiley.

Almost immediately, the Guarneri made now-classic recordings with the pianist Artur Rubinstein for RCA. Later established as one of the primary American quartets, the group was the subject of the 1989 documentary High Fidelity: The Adventures of the Guarneri String Quartet and the book The Art of Quartet Playing with David Blum.

For all of Mr. Soyer's Philadelphia affiliations, he was the only quartet member not to have been educated at Curtis.

His teaching style at Curtis was often witty and sometimes brutally honest, said Margo Tatgenhorst Drakos, a former student and family friend. "He hated dead notes. He taught you that you have to project, and that the vibrato matches the expression of the phrase. The most important thing he taught was, you teach yourself."

Musically, he was not demure. Guarneri violist Michael Tree said, "He provided us with a rich and full bottom register upon which we could lean and always feel encouraged to give our all."

Though Mr. Soyer's choice of tempos slowed during the quartet's final years, Tree said, "Dave could be like a charging horse, and that inspired us."

He is survived by his wife, Janet Putnam Soyer; sons Daniel and Jeffrey; two granddaughters; and a sister.

A service will be at 3 p.m. tomorrow at Riverside Memorial Chapel, 180 W. 76th St., New York City. A memorial at the Curtis Institute will be announced.

Samples of his solo performances can be heard at www.instantencore.com/davidsoyer