The Robert N. Miner Auditorium in San Francisco's new $65 million SFJAZZ Center is the first concert hall in the United States built just for America's native musical form-- and that presented some special challenges to acoustic designer Sam Berkow.
He says the hall needs to accommodate a wide range of styles--from solo piano with very light amplification all the way to bold, brassy big bands.
Berkow showed me around the Miner Auditorium a few weeks a while the room was still under construction. Pretty much every surface has some sound enhancing trick up its sleeve, including the acoustical canopy, like a big rigid sail, above the stage.
"There are really only three things you can do with sound." Berkow explained. "You can absorb it, you can redirect it, or you can diffuse it. And the canopy does all three."
Berkow and his crew had set the canopy at just the right angle earlier that day, positioning it so it would reflect and diffuse sound evenly to all 700 seats in the hall.
The goal might best be described as giving each listener the feeling they're in an intimate jazz club, minus the clinking cocktail glasses.
In designing the hall's sound, Berkow got to use a tool not available in a typical symphony hall: a sophisticated sound system built around two massive arrays of speakers built by Berkeley's Meyer Sound Laboratories
Seeking an Acoustic Balance
Berkow spent weeks working with computers and acoustical software he designed himself to fine-tune the speaker arrays, a task made more challenging because the room is asymmetric. He's put more speakers on the left side, and just three on the right side where there's a balcony.
For all the technology at his disposal, Berkow is at heart a jazz lover who wants the sound engineers at future shows to use the speaker system with discretion. "We're hoping that everyone in the hall is hearing sound live from the stage," he said.
He says the the sound system is capable of blasting the audience with rock and roll, but mostly he expects it to be used to balance the sound. "Letting an acoustical bass keep up with trumpets and a horn section." Berkow said. "Letting a singer sing on top of a full band, and to hear the nuance and interplay of the musicans."
'Go for the Home Run'
Berkow says SFJAZZ founder Randall Klein defined the acoustic goals for the new concert hall early on: " 'Go for the home run. They'd rather fail than go for something mediocre.' "
Everyone will notice if Berkow fails to hit that homer. But even a grand slam may bring little notice.
Cecilia Englehardt is director of production for SFJAZZ. She says she wants audiences to talk about the music after a show, not the acoustics."So the audience is ignorant--does not even think about the room or the sound," she said. The goal is to make " the sound system and the room become transparent. They go away."
On Monday, as the new center I sat a few rows up in the orchestra as the SF Jazz High School All Stars
rehearsed for a performance. They weren't miked, and they sounded great.