Eighteen people stood in a circle, singing their hearts out and listening to their different voices mesh into one. Forgetting everything from world suffering to the homework they had due, the stress of the day lifted as their combined sound grew louder, one voice compacted from the several Shalhevet HIgh School students who have a burning passion for singing.

That was the scene in the Music Room Nov. 29 as alumnus Seth Samuels ’06 ended a month of special rehearsals with the Shalhevet Choir. From breathing work to a pitch accuracy exercise called “the nuke,” new techniques he brought had intensified the group’s sound and made simple warm-ups give members the chills.

A graduate of Columbia University and Jewish Theological Seminary in New York, Seth returned as a temporary volunteer coach this fall to help the choir learn new musical skills. In nine rehearsals, he revolutionized the choir’s pitch, tone, tempo and rhythm with his knowledge from leading Columbia’s Jewish a capella group, Pizmon.

“It was pretty amazing,” said senior and soprano Ariella Joffe. “He’s an alumni but he also has college experience and he was able to teach us all new things. He was able to not only help Mrs. Keene out, but help us all individually with what we need to work on.”

Seth e-mailed Mrs. Keene in October with the idea to help out the choir and started coming to practices later that month, attending nine in all. He is currently enrolled in both the law school and a graduate urban planning program at UCLA.

“I was in my college a capella and I loved it, and when I graduated I kind of missed it,” Seth said in an interview. “I thought instead of starting my own a cappella group in grad school, it would be nice to go back to Shalhevet and see if Mrs. Keene would like some help or a new perspective.”

This perspective included teaching the choir new warm-ups, breathing exercises, and ways to navigate the intervals between notes more accurately. Seth also worked one-on-one with individual students who he’d pull out of rehearsal for a few minutes, and sang with the boys during practice to help them get the notes faster.

“He added something fun,” said senior Adam Sharabi, a bass, “instead of simple scales that we did for warm-ups every time. He was funny and he helped us out with a lot of minor, technical things that Mrs. Keene didn’t have time to help us with.”

Seth is also an accomplished cellist, and Mrs. Keene said Shalhevet’s then-new choir was his first experience with choral music. To have him return and raise the level of the group was an experience she called “very sweet.”

“We always say we learn from our students as much as we teach them, but it rarely happens in such an obvious form,” Mrs. Keene said.

“He worked with us on vocal production and choral tone, which is partly blend and partly more than blend,” she said. “He gave us breathing exercises far superior to what we were doing, and the result is that the choir came up to a level in November that we have been lucky to reach in May.”

For his part, Seth seemed to enjoy it as much as the students did.

“They’re a really great bunch of students,” he said. “It’s really hard to concentrate after such a long day, but they were really fun to work with. They have a lot of promise.”