Acoustic Magic Voice Tracker I User manual

INSTRUCTIONS
General Setup
Connect the power and audio cables to their appropriate
jacks on the back of the Voice TrackerTM Arra (see
Figure 1). Plug the power adapter into a standard 110-
volt wall outlet and connect the other end of the audio
cable to the “mic in” input on our computer’s sound
card. The adapter supplies 6V DC power (center pin
positive) to the microphone.
Figure 1 – Audio and Power Cable Connections
The Voice TrackerTM Arra ma be used as the audio
input device for a variet of speech and multi-media
applications. Man of the software packages which
utilize a speech input have setup tools, which allow ou
to specif that ou are using the “mic In” connection on
our soundcard and to adjust the sound level (volume)
automaticall . Please refer to our specific application
software for details. To adjust the volume or input
selection manuall on a Windows PC, see the Adjusting
Your Soundcard section at the end of these
instructions.
Positioning
Aim the arra in the direction of the desired talker(s).
When properl positioned, the talker will be able to see
all 5 green position indicators.
Figure 2 – oice TrackerTM Array Front iew
The Voice TrackerTM can be tilted up or down to facilitate
mounting on the desktop (tilted up) or on the monitor
(tilted down). For speech recognition applications, the
desktop position will exhibit slightl better performance.
If ou mount it on top of the monitor, makes sure it is
secured so it doesn’t fall off. The Voice Tracker can be
mount on the ceiling b removing the weight in its base,
and using the 4 screw hole in the base.
Mode Switches
The Voice TrackerTM has 4 operational modes, selected
b two switches: the Field switch and the Location
Dependent SquelchTM (LDSTM) switch (see Figure 3).
Figure 3 – Field and LDSTM Switches
The Field switch determines the scanning range of the
arra . In the wide-angle mode, the Voice TrackerTM will
scan +/- 90 degrees. This is useful if the user desires to
listen to an entire room. In the narrow-angle mode, the
arra will scan +/- 45 degrees. The narrower scanning
range helps to reduce the impact of undesired talkers
and noise sources outside the region of interest. Note
that the Voice Tracker does pick up sound from behind,
giving it a full 360 degree field of view. However, it is
more sensitive in the forward direction.
When the LDSTM switch is set to On, the Voice TrackerTM
will turn off during periods of silence and when the sound
source is located outside the arra ’s reception region as
determined b the Field switch. The arra turns on
again ver quickl when the user resumes talking.
When used together with the narrow field of view, the
LDSTM can be emplo ed to ignore unwanted sounds.
Once the talker pauses and the Voice TrackerTM turns
off, the arra will onl turn on again when sounds come
from within the +/- 45 degree listening area (see Fig 4).
Figure 4 – Listening Area
For speech recognition applications, when the limited
scan range and LDS are on, the generation of spurious
words or commands from sources outside the listening
area will be reduced. However, since the beginnings of
words ma be clipped off, recognition accurac ma
suffer. The user should decide whether this feature
improves performance in their particular noise

environment. In general, we recommend LDS off and
the narrow field of view for speech recognition
applications.
Using a narrow field of view and LDSTM can also be
useful when teleconferencing. If the incoming talker’s
speech is pla ed through loudspeakers positioned
outside the +/- 45 degree listening area, the arra will
turn off when onl the far-end talker is active, thereb
minimizing echo in the channel.
Position Lights
The green position lights provide feedback on the
operation of the arra . The indicate where the arra ’s
listening beam is pointing. When the arra recognizes a
relevant sound, one of the 5 lights will be illuminated.
The individual lights correspond to the range of potential
sound source locations. For example, if a talker is
directl in front of the arra , the middle light will be
illuminated. If the talker is to one side, a light on that side
will turn on. If the talker moves across the field of view of
the arra , the lights will track the talker’s motion. When
two users are sharing the arra , the light will indicate the
direction of the active talker. In the narrow scanning
range mode, onl three lights are active. When there is
no active talker, the lights ma flicker as the Voice
Tracker TM searches for a talker.
When the LDS is on, the indicator light will be illuminated
onl when there is sound activit within the designated
listening area. With the LDS off, a light will remain on
continuousl through both speech and silence periods.
In the event that no lights are on and the LDS mode is
off, it is possible that the arra is not plugged in or is
working improperl .
Using the oice Tracker for Speech Recognition
Since the Voice TrackerTM operates differentl from other
t pes of microphones or audio input devices, ou should
retrain our speech recognition s stem after connecting
the arra and adjusting the soundcard gain level. This
will allow ou to more effectivel utilize the improved
sound qualit produced b the Voice TrackerTM and will
improve the overall performance of our speech
recognition software. Be sure to select mic in during the
“New User” setup. Personalized vocabular can usuall
be transferred to the retrained “User”.
Adjusting Your Soundcard
On our Windows PC:
1. Go to Start button, Programs, Accessories,
Multimedia (or Entertainment), then volume control.
2. Make sure the Mic In’s mute is checked.
3. Go to Options, then Properties, select the circle next
to Recording.
4. In the ‘Show Volume Controls’ region check the box
next to Mic In and then click OK.
5. Check the Select box under Mic In and set its
volume to an appropriate level for our soundcard.
Be careful not to set this volume level too high. This
will cause clipping.
6. Exit recording control.
Trouble shooting:
- Audio cuts out: Be sure LDS switch is in off
position
- No audio. Check whether green lights track the
talker. If so, the problem is probabl in the
computer. Make sure it is looking for recording
input where the Voice Tracker is connected (mic
in or USB)
FCC & CE Mark Compliance
This equipment has been tested and found to compl the
limits for a Class A digital device, pursuant to part 15 of
the FCC rules as well as the CE Mark rules. These limits
are designed to provide reasonable protection against
interference when the equipment is operated in a
commercial environment. This unit generates, uses and
can radiate radio frequenc energ , and if not installed
and used in accordance with the instruction manual, ma
cause harmful interference with radio communications.
Changes or modifications not expressl approved b
Acoustic Magic could void the user’s authorit to operate
the equipment.
This digital apparatus does not exceed the Class A limits
for radio noise emissions from digital apparatus as set
out in the Radio Interference Regulations of the
Canadian Department of Communications.
If ou have further questions, e-mail us at
[email protected]
Or call 978 440 9384.
ACOUSTIC MAGIC, INC.
35 Peakham Road
Sudbur , MA 01776
www.ACOUSTICMAGIC.com