Acoustic Magic Voice Tracker II™ Array Microphone

Since the Voice Tracker array microphone can pick up talker throughout the entire room, it has often been used for conferencing applications
It became clear from customer feedback that incorporation of a high-quality acoustic echo cancellation (AEC) algorithm would broaden the Voice Tracker's application by enabling full duplex VoIP based conferencing at a fraction of the cost of conventional conferencing systems.
The addition of a high-quality AEC algorithm to our internal DSP is the main differentiating feature of the Voice Tracker II ™ Array Microphone, but it has several other attributes as well.

Scanning “Listening Beam”

Unlike conventional microphones, or first generation array microphones, which have a fixed "listen" direction, Acoustic Magic Voice Tracker™ Array Microphones automatically locates the active talker and electronically steers a “listening beam” in that direction. It can steer its “listening beam” over a 360 degree range, creating a wide field of view. For Meeting Recording or Lecture Capture or Conferencing Applications, the Voice Tracker™ Array Microphone captures all the participants since its “listening beam” moves from one talker to the next in milliseconds. For speech recognition applications, it is no longer necessary to sit rigidly in front of the microphone. The user is free to lean backwards, sideways, or even move around.

Spatial Filtering for Noise Reduction

The Voice Tracker™ Array Microphone improves signal-to-noise ratios in two ways.

First, its digital signal processor creates a listening beam (like a searchlight) that focuses on the talker and spatially filters noise from other directions.
Second, its proprietary noise reduction algorithms filter out background noise and reverberations that are present in the acoustic environment.

Turns inexpensive VoIP based telephony systems like Skype and Adobe Connect into Conferencing tools.

A crucial audio requirement for conferencing is the elimination of acoustic echo (sound from the far end talker picked up by the open mic and sent back). The Voice Tracker II ™ Array Microphone’s internal AEC algorithm provides performance that rivals or exceeds that of AEC boxes costing several thousand dollars. Connect the Voice Tracker II ™ Array Microphone to your PC based VoIP software and eliminate the need to use headphones; all the near end talkers will be heard, even if they talk softly or are far away from the mic, and the far end talker will hear no echo.

Acoustic Echo occurs when an open mic picks up a far end talker (from the loudspeaker) and sends it back to the far end talker (as an echo). In the above charts, the bottom chart shows the audio from near end and far end talkers transmitted by the Voice Tracker II with acoustic echo cancellation off. The top chart shows a similar audio transmission with the AEC turned on.

Improved Portability

The Voice Tracker II™ is significantly smaller than the Voice Tracker I. The Voice Tracker II’s primary audio output is USB and it is powered by its USB connection, eliminating the need to be connected to wall power. Not only does this remove the need to carry the wall power converter, it eliminates the need to have different wall power converters for different countries.

Talker Location Signal

Since the Voice Tracker automatically and electronically steers a listening beam to the active talker, it knows the location of the talker. In the Voice Tracker II ™ this information is made available outside the DSP as a RS 232 serial word through a DB-9 Jack. A sophisticated customer can use this information to point a camera, or turn the head of a robot toward the talker. Note that Acoustic Magic does not provide any algorithms for the use of the location information.

Voice Tracker II™ Specifications

Range:20+ feet for meeting recording (depends on acoustic characteristics of the room).
AEC Performance:
G.167 Compliant
70 db of echo cancellation in single talk
40 db of echo cancellation in double talk
Convergence time of less than 100ms
Sample rate: 48KHz
Primary audio output: USB
Secondary audio output:
Mic level or Line level (switch controlled) 3.5mm ministereo jack
6ft male/male audio cable (optional) Same signal on tip & ring 500 ohm output impedance
Talker location signal accuracy: 5 degrees
Frequency Response:
100Hz to 11,250 Hz
Physical Dimensions:
Length: 11.5"
Height: 1.5"
Weight: 0.75lbs
Power Equipment: Powered by USB (wall-powered converter optional)
5V DC
400 ma
Compatible with a variety of operating systems including:
Apple/Macintosh : Mac OS, Mac OS X
Microsoft : Windows 3.x, Windows 95,Windows 98,Windows NT, Windows 2000,Windows ME, Windows XP, Windows Vista, Windows 7

Downloads :

• Instruction Manual