Popular Science - USA (2019-10)

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ceilings, bare floors, and walls and furniture made of hard,
sound-reflective materials like concrete, tile, metal, plaster,
and glass, which send noise careening around the space.
At the same time, they merged dining rooms with
open kitchens and bar areas, and cranked the music. Few
reckoned with the sonic implications of these choices,
according to Lily Wang, an expert in architectural acous-
tics and past president of the Acoustical Society of
America, which shares research and develops standards
for everything from hearing aids to classroom noise.
“Architects aren’t trained to think about sound; they’re
trained to think visually and spatially,” says Wang, who
is participating in a nascent effort within the ASA to
establish guidelines for restaurants.
Plus, some level of loudness seems to benefit the bottom
line. Marketing research suggests that customers prefer
places with lively background music, and they drink more
alcohol and eat faster when the volume rises, boosting ta-
ble turnover and revenue. Never mind that other studies
suggest noise dulls our taste buds and leads us to favor fries
over side salads and make other indulgent menu choices.
The racket is insidious in other ways too. As tables fill
up and drinks flow, the ambient sound increases, causing

diners to unconsciously raise their voices. This reflex,
known in the acoustics industry as the Lombard effect,
can start a vicious cycle. There’s no scientific consensus on
the decibel level that triggers the phenomenon, but a 2018
study in a simulated restaurant found that voices started to
swell when the volume ticked above 57.
At Meyer Sound, senior scientist Schwenke believes that
“if the person next to you is intelligible and the people far
away are less intelligible,” then your brain perceives less
of a threat to you being understood, and you’re less likely
to escalate to a Lombard cascade. Their challenge was to
somehow modify Constellation to enhance each table’s
conversation while simultaneously fuzzing out the rest.
“It was an experiment,” Meyer says of the effort, “but I
knew there was a tremendous amount we could do.”

THE NEXT RECORDING THEY PLAY IS FROM COMAL. OWNER
John Paluska is a rarity among restaurateurs: As the former manager
of the band Phish, he’d thought a lot about sound before opening
the eatery in 2012. He hoped to create a fun ambience but knew that
his design choices came with a real noise risk. He also wanted some
acoustic control to fashion a high-spirited vibe near the bar and
quieter areas toward the back of the place.
Paluska’s architect knew the Meyers because she and Helen had
served together on a local school board. Helen showed Paluska some
sound-absorbing panels and chatted about music systems. Then she
demonstrated Constellation, which so far had been used only in concert
halls to overcome sonic shortcomings, such as high-frequency tones
from flutes and violins dying before reaching the final rows of seats.
At its core, Constellation is a sleight of hand pulled off by tweaking
and redistributing reverb: the echoes we hear when sound waves spread
from their sources and bounce from one surface to another. Absorbing
these pings keeps audio from lingering, while digitally adding just a cou-
ple of seconds of echo can make a dead space in an auditorium ring like a
cathedral nave. Helen calls this effect “invisible architecture.”
But restaurants present a more nuanced challenge. The sound
doesn’t come from a stage; it comes from everywhere—and not
every one wants to listen to the same thing. For Constellation to
help in this setting, the Meyer team would first need to deaden the
space as much as possible. From that base-
line, the system could capture, modify, and
precisely tweak the clang from kitchens
and noise from neighbors so diners could
hear their own conversations.
Paluska was fine with being a guinea
pig. Comal was still just a Berkeley store-
front stripped down to its studs. The Meyer
team began by squeezing in sound dampen-
ing wherever they could. Between exposed
Douglas fir beams, they put 2-inch-thick
rigid fiberglass insulation with a matte
black finish so it would disappear. They
hid wood-fiber insulation that resembles
shredded wheat behind burlap wainscot-
ing. And they printed the artwork—large
abstract paintings and oversize Oaxacan
street photography—on acoustically porous fabric stretched over
sound-absorbing material in an aluminum frame. The Meyers call
this proprietary product Libra panels.
Next, they wired up Constellation’s skeleton of 28 microphones and
95 speakers. They placed the mics as evenly as possible to cover each
table while avoiding high-noise areas like the open kitchen. They posi-
tioned speakers so diners wouldn’t hear any of the outputs in isolation,
instead catching a seamless sonic mix. The crew networked all these
components through Constellation’s brain: a collection of digital sig-
nal processors that can each handle 100 gigaflops of data and combine
to roughly equal the power of a dozen MacBook Pros. The computer
knows which sounds come from which microphones, and lets Comal
staff alter the sonic setting in real time from its iPad interface.
Imagine that you and a date are there on a crowded, buzzing Fri-
day evening. Microphones above the table capture the vibrant

76 WINTER 2019 • POPSCI.COM

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