Stephen D. Ambrose, Founder and Head of Audio Technology
Stephen Ambrose is the original inventor and industry pioneer of the wireless in-ear monitor (IEM) systems currently used in nearly all rock concerts today. These devices are often seen in the ears of performers on American Idol, and they predate and were emulated by devices such as the Sony Walkman and Apple iPod ear buds. The story of their evolution, and that of the burgeoning personal listening device market which followed, is an interesting one.
In 1965 at the age of 13, Stephen Ambrose began his professional
singer/songwriter career at the invitation of producer C.B. Andersen to
record at Nashville's Television, Radio and Film Corporation (TRAFCO)
studios. Johnny Cash was also recording next door and Stephen was
invited to listen. Dazzled by how magical Cash’s voice sounded in the
headphones when mixed through the studio’s echo chamber, he dashed home
and set about modifying old tape recorders discarded from nearby
Vanderbilt University where his father taught, in an effort to bring
this “magic” to his own performances at school. The result, though
crude, was the first IEM system.
1960s consumer in-ear devices were limited to small, low fidelity
transistor or crystal radio earpieces. In addition to their narrow
bandwidth and high distortion, these earpieces provided only hard,
extremely uncomfortable "light bulb" shaped ear tips. To reduce the
discomfort, Stephen replaced the hard ear tips with hollowed-out
swimmer’s ear plugs and clay in an effort to fashion an ear mold. Over
the next 6 years Stephen performed prolifically throughout the south
with various high school and college bands and recorded demo tapes of
his original songs at Huntsville’s Muscle Shoals Studios for producer
Jerry Masters. Always on the lookout for smaller and smaller speakers
affording broader bandwidth and less distortion, he continued developing
his IEMs between performances and finally signed his first Hollywood
record deal with Andy William's Barnaby Records label in 1971. The
popularity of his first solo album "Stephen Ambrose - Gypsy Moth” and
his hit single “Friend” allowed him to play large performance venues
which , importantly, also required much louder stage volumes.
In those early days before IEMs, rock stage volumes were notoriously
high and extremely tough to sing over, and often left everyone’s ears
ringing for hours afterwards. After a string of such performances,
Stephen redoubled his efforts to make his ever evolving in-ear-monitor
invention wireless, which he knew was the key to their true usefulness
and success on stage. Looking for small transmitters that could be used
with portable radios, Stephen obtained an early wireless guitar
transmitter developed and used by John Nady and his Captain Nasty Band
which became the first popular device of its kind. After a few
modifications, Stephen introduced the very first high-fidelity
custom-molded in ear monitors while performing at a popular night club
in Hollywood in early 1976.
Sharing a booth with Nady at the ‘78 NAMM convention in Anaheim, Stephen
introduced his IEM invention to hundreds of professional musicians and
engineers attending the show. Shortly after, his "SoundSight
MicroMonitors" obtained broad use across all the major Hollywood film
scoring stages, embraced by top percussionists Larry Bunker, Victor
Feldman, Emil Richards, Kenny Watson and Joe Pocaro, whose avid use
quickly popularized them amongst a majority of musicians involved in the
scoring of soundtracks for top movies such as Star Trek, Escape from
Alcatraz, ET and hundreds more. By the May 1982
BAM magazine interview,
with David Zimmer (authorized biographer for Crosby, Stills, Nash and
Young) Ambrose was engaged to provide and engineer his in-ear monitors
for world concert tours including Stevie Wonder and Simon and Garfunkel
and had already introduced in-ear monitoring to Joni Mitchell, Herb
Alpert, Diana Ross (1982 Super Bowl Performance), John McLaughlin, Jim
Messina, Olivia Newton John, Patti LaBelle, Bob Weir, Missing Persons,
Michael MacDonald, Mel Torme, and many other top box office artists of
the day. In the following decades, he continued introducing his
invention while touring and engineering in-ear monitors for Michael
Bolton, Clint Black, Reba McEntire, Al Jarreau, George Jones, George
Straight, Lori Morgan, Steve Miller, Mr. Big and Rush, Anita Baker,
Great White, Bon Jovi, Engelbert Humperdink, Julio Iglesias, and dozens
more, and was engaged for in-ear recording and television studio
monitoring performances by the likes of LL Cool J, Guns n Roses, Pink
Floyd (Jim Keltner), Lionel Richie, Chick Corea, Dave Weckl, John
Patitucci, Whitney Houston and many others. He provided and engineered
the first use of in-ear monitors for the Academy Awards, Grammy Awards,
American Music Awards, Saturday Night Live, The David Letterman Show,
The Soul Train Awards, The Johnny Carson Show, The Arsenio Hall Show,
and many movies including Keanu Reeves and Alex Winter in Bill and Ted's
Bogus Journey. He wirelessly delivered formal speech line cues for
Stevie Wonder's nationally televised speeches in favor of the Martin
Luther King national holiday (given from the steps of the Capitol
Building to the thousands marching on Washington), and was present at
the White House Rose Garden signing of this bill by President Reagan.
Also a professional performer, Ambrose continued to
write and record and often performed lead or background vocals in the
studio or on stage for many artists including Brian Wilson, Bobby
McFarrin, Geoffrey Osborne, Jimmy Web, Denise Williams, Melissa
Manchester, Kevin Carpenter, Roger McGuinn, Holland-Dozier-Holland,
Siedah Garrett, Carol Bayer Sager (NAS Hall of Fame Awards, Beverly
Hills Theater, 1986-87-88), David Pomeranz, Edgar Winter, Nicky Hopkins,
Frank Stallone, Gayle Moran and many more.
In addition to inventing and engineering the first IEMs, Stephen also invented the first widely used professional instrument-mounted hypercardioid condenser microphones (called SoundSight MicroMics) used by David Sanborn, Tom Scott, Al DiMeola, Lee Ritenour, Richard Greene, Freddy Hubbard, Steve Kujala, Tim Weisberg, Victor Feldman, Terry Bozzio, David Savage, Michael Brecker, Kenny G, Doc Severinsen, Al Vizzutti, Lee Oskar, Stanley Clarke, etc., which were often used in the same performances involving his IEMs. His work designing custom microphones contributed greatly to his understanding of audio sound pressures developed in the ear canal by personal listening devices. He also introduced and taught hundreds of monitor engineers the art of live in-ear monitor mixing, having become expert at this under the direction of Roy Hallee with whom he toured during the early 1980s Simon and Garfunkel world tour which spanned 2 1/2 years and 4 continents, including the Middle East.
Since there were no high fidelity insertion audio devices available or
in use in the '60s and '70s when Ambrose began his quest for
studio-quality on-stage monitoring, his ultimate coupling of superb
broadband audio transducers with custom ear molds had no precedent.
Although the sound was extremely impressive at first, prolonged use and
close inspection by himself and others such as Stevie Wonder revealed
serious IEM problems with audio fatigue, frequency response, dynamic
range, occlusion effect (the head-booming sound of one’s own voice when
the ears are sealed), and other significant properties which do not
exist in open-ear or natural acoustics. Widely accepted today, musicians
overlook that while IEMs can be lifesavers when it comes to excessive
floor monitor volumes, they deliver other significant excesses and
potential harms which are described in Sound Reproduction within a
Closed Ear Canal: Acoustical and Physiological Effects -Ambrose, Gido (presented at the 130th AES Convention in London on May 14th)
and which are so effectively and eloquently solved by the inventive
devices this paper heralds.
The deployment of IEMs in world tour situations no longer required the
costly air transport of thousands of pounds of heavy stage monitors,
amplifiers, and endless racks of outboard gear and EQs. As a result,
Ambrose was able to direct the resulting surplus transport funds into
the acquisition of top quality professional recording consoles, and
often toured with two 48 track stereo mixing consoles, 4 Lexicon 224x
reverb modules, as well as up to 17 programmable stereo transmitters.
And yet with all the best equipment and access to top studio engineers
such as Roy Hallee, and all the top house engineers for Claire Bros, TFA
Electrosound, Maryland Sound, and many others, it soon became obvious
that the harmful over-excursions, audio fatigue and other ills attendant
upon the making of a closed speaker cabinet out of the ear canal (which
all conventional IEMs and many ear buds certainly do) could not be
rolled off or notched out by the best equalizers, limited or compressed
away by any combination of dynamic processors, or effectively mitigated
in any way whatsoever. As we have now discovered, this can only be done
by addressing the problem at its actual root.
Just why these unwanted and potentially harmful conditions were not able
to be engineered "out of the mix" by the best equipment or engineers was
the subject of a lifelong pursuit for Ambrose, and subsequently for the
fellow scientists and engineers who came to take his incessant searching
seriously. Their discovery, as published in the 130th AES Convention in
London paper “Sound Reproduction within a Closed Ear Canal: Acoustical
and Physiological Effects -Ambrose, Gido” reveals the
physiological phenomena which can cause users of personal listening
devices to endure excessive, potentially harmful volumes levels, and
importantly why they often do not want to turn them down.