Not far from the same Boston Harbor where the American Revolution was
born, there’s a small warehouse complex
that houses Source Audio—a band of sonic
inventors who’ve embarked on a unique
musical mission they feel is also pretty revolutionary. The Woburn, Massachusetts, company sprang onto the effects scene in 2005
with pedals unlike any the world had seen. In
contrast to the vintage reimaginings you see
from a lot of stompbox makers, they came
out with the Hot Hand wah and Hot Hand
phaser/flanger—thoroughly modern designs
in molded-plastic casings that spoke more to
the computer age than the Woodstock era.
But looks were only the beginning: These
effects enabled a guitarist to control parameters by waving around a ring attached to
their finger. But, as it goes for many new kids
on the block, Source Audio found that the
road forward wasn’t easy.
The Human League
It all began at Analog Devices, Inc. (ADI),
a designer and manufacturer of analog
and digital signal processing (DSP) semiconductors (chips) based in Norwood,
Massachusetts. ADI is one of the world’s
largest producers of mixed signal “system on
chip” designs that have an entire analog and
digital signal path on a single silicon chip.
While working in a chip development
group at ADI, future Source Audio presi-
dent Roger K. Smith met Bob Adams, a
legend in the world of analog-to-digital and
digital-to-analog converter development.
“Bob recognized unique opportunities to
put more and more smarts onto the con-
verters,” says Smith. “This is what ulti-
mately formed the chip we use: analog in
and analog out, with an enormous amount
of processing power in-between.”
ADI’s high-performance SigmaDSP
audio processor is at the heart of the
SA601 chip used in Source Audio pedals.
While some competitive digital devices
use 16- or 24-bit audio processing, the
SigmaDSP uses a 56-bit processing path,
ensuring less digital distortion.
But Source Audio’s story is as much
about people as technology: As any guitarist
or bassist can attest, it doesn’t matter how