HOLLYWOOD — Rehearsal began the same way for forty years, with Lorraine Sisk striking a single note on an old pitch pipe and waiting, without a word, until forty amateur singers found it and the room settled into one sound.

Miss Sisk, who founded and led the Cahuenga Community Chorus, a volunteer choir that met in church halls and rented rooms across Hollywood, died February 27 at a hospital in Los Feliz. She was 89. A longtime friend said the cause was a stroke.

The chorus was never professional and was never meant to be. Sisk built it in 1979 out of whoever showed up — retired teachers, a mail carrier, a couple of out-of-work actors, teenagers sent by their parents. She held auditions but almost never turned anyone away; the audition, singers came to understand, was less about whether you could sing than about whether she could teach you to.

“Lorraine could take a room full of people who’d been told their whole lives to just mouth the words, and six weeks later you’d weep to hear them,” said Bernadette Ochoa, who sang alto in the chorus for twenty-five years. “She didn’t care if you had a great voice. She cared whether you listened. That was the whole thing with her — listen first, then sing.”

Lorraine Sisk was born in Fresno in 1935 to a family of church musicians and trained as a music teacher, spending her days in public-school classrooms and her evenings, for most of her adult life, in front of the chorus. She never married and spoke of the singers as a kind of family, one that renewed itself as older members died and new ones drifted in.

She programmed without condescension, mixing folk songs and spirituals with pieces she was warned were too hard for amateurs, and was usually proven right to try them. Concerts were held wherever she could arrange a room — a Lutheran sanctuary on Gower, a theater’s bare stage on a dark Monday, once, memorably, a parking structure whose echo she decided to treat as an instrument.

The chorus intends to continue, its members said, though no one imagines replacing her so much as carrying on in her manner. They have already agreed on one thing: rehearsals will still open with the pitch pipe.

Miss Sisk is survived by a brother, Warren Sisk, of Fresno; two nieces; and several hundred former singers, by the chorus’s own rough count, scattered across six decades of Hollywood.

Her pitch pipe, a battered chromatic instrument she had used since the 1960s, will stay with the chorus. At the first rehearsal after her death, her friends said, the singers passed it hand to hand without quite knowing why, each holding it a moment before it went back in its case, unblown.