Application Note #2
Corporate Audio/Video Presentations with the MTI-3
Benefits For The Corporate A/V Professional
The Miles Technology MTI-3 TriSonic Imager
provides a wide range of benefits that can enhance
your audio and "audio for video" in the corporate
market. Its patented TriSonic Imaging process does
not dynamically modify the signal; instead it provides
clean, open, and uncolored left-center-right sound
with full-bandwidth (20 Hz to 20 kHz) surround
The TriSonic center channel adds another dimension
to the program material. It pulls out subtleties in the
mix, and provides a fuller sound with a true stereo
image delivered to every seat even to listeners
located at the extreme sides.
The center channel firmly anchors dialog or other
central sounds to the center of the video screen.
The sound of the center channel can be fine tuned
with the MTI-3. For example, vocals in a stereo mix
can be emphasized or de-emphasized as needed with
a simple front-panel adjustment. And a live vocal
channel can be a "point-source" through only the
center channel or distributed to the loudspeaker array
Also, with a simple adjustment, the apparent stereo
soundstage can be widened beyond the left and right
loudspeakers, for a dramatic "wide-stage" effect.
The surround channels add further depth to the
sound and can enhance or emphasize all types of
effects. The overall impact of surround sound draws
the audience further into the production. In most
cases, small low-power loudspeakers are effective
Using the SpreadSound process, mono sources can
be enhanced to sound like high-quality stereo sound.
The MTI-3: A Brief Description
The MTI-3 is a high-fidelity multichannel stereo audio processor. Using TriSonic Imaging technology, it
creates left, center, and right outputs from any standard stereo signal. Combined with correct
loudspeaker placement, the MTI-3 enables outstanding stereo imaging performance, with precise
sound-source localization, over a very large listening area. Front-panel controls allow optional
adjustments to further tailor and optimize the sound to meet any need. The unit also provides
full-bandwidth, high-quality surround outputs for professional surround-sound systems.
Field Application: Fortune 500 Corporate A/V
Chas Gerber has spent more than 20 years designing
systems and mixing live productions; for the last 10
years he has specialized in corporate A/V sound. He
serves a Fortune 500 clientele, including Reebok,
Lotus, and several others.
He first used the MTI-3 for Lotusphere '96 at Disney
World's Dolphin Hotel, a show for more than 7,000
attendees featuring a Cirque-du-Soliel-type theme.
Gerber's goal was to supply high-quality stereo sound
to the entire audience including those seated at the
extreme left and right. Two large video screens flown
across the soundstage further complicated the
Mono Doesn't Cut It
Mono sound would have been the easiest solution,
but the show was music-intensive and included
stereo sources. Gerber has tried other solutions for
situations like this, such as alternating left and right
clusters, but with disappointing results. Sometimes
static designs like this are ruined by the inevitable
last-minute seating configuration changes.
His optimum design utilizes left, center, and right
EAW KF Series loudspeaker arrays fed by an MTI-3
TriSonic Imager. The left and right loudspeaker
clusters were positioned to the extreme sides of the
video screens, and the center cluster was flown
between the screens.
The results were spectacular, according to Gerber,
with clean, open stereo sound supplied to every seat
while the sound system stayed nicely out of the way.
The three loudspeaker arrays kept the sound stage
tightly linked with the video screens. Using the
MTI-3's TriSonic Balance control, he was also able to
push the left and right sound field wider than the
room when appropriate.
At the 1996 Reebok Global Summit, Gerber faced
another problem that he solved with the MTI-3. An
important part of the show was the premiere
presentation of several new Reebok TV commercials.
Mixed at post houses around the globe, the
soundtracks of these commercials are plagued with
Vocal Problems Solved
As Gerber explains, "Sometimes you really need to
bring the vocal out, and sometimes it needs to be
pushed back. With the MTI-3, we could tweak the
vocals as necessary, and on the fly, because the unit
is so easy to operate."
He has devised a convenient method for patching the
MTI-3 into the mixing console, usually a Yamaha
PM-3500. Using the matrix section of the console, he
assigns left/right playback to left/right master faders.
The MTI-3 is inserted into this path; that is, the
left/right insert sends are routed to the left/right
inputs of the MTI-3, with the unit's left/right outputs
then routed back via insert returns.
Meanwhile, the MTI-3's center output is routed to
subgroup 8 of the console. With this configuration,
left, right, and subgroup 8 (center) can all be dialed
into the console matrix and assigned to the
loudspeakers. See diagram below.
A New Solution
"My challenge as a sound designer serving this
market is to always be open to change, to always
seek new solutions like the MTI-3. This ensures
consistently successful shows, and in turn, ensures a
very happy client," Gerber concludes.
For more information or additional application notes
regarding TriSonic Imaging, the MTI-3, or other
Miles Technology products, call 800-280-8572 or
write to 1826 S. Third St., Niles, MI 49120.