Applications of Voice Tracker Array Microphones
Voice Tracker array microphones were designed with the objective of creating a low-cost, reliable, easy-to-use microphone that can capture talkers throughout the room at ranges of up to 30 feet with a 360° field of view. Several Voice Trackers can be combined to increase the pickup range. Most users connect Voice Trackers to a computer for use with applications such as VoIP conferencing, meeting and lecture recording, automatic speech recognition, etc. But it can also be connected directly to devices that accept analog microphone input such as handheld recorders, PTZ cameras, mixers, etc.
The Voice Tracker™ Array Microphone automatically locates the active talker and electronically steers a “listening beam” in that direction. It can direct its “listening beam” over a 360 degree range, creating a wide field of view. Voice Trackers are essentially unidirectional microphones with an omni directional field of view. The audio output from six or eight discrete microphone elements goes to a digital signal processor inside the Voice Tracker. The Digital Signal Processor (DSP) performs the beamforming, noise reduction, acoustic echo cancellation, etc. algorithms. The resulting processed audio is outputted through a 3.5 mm analog audio jack or USB.
The Voice Tracker™ I has eight microphone elements, and provides an analog audio output at mic level through a 3.5 mm Jack. It is powered by a wall power supply.
The Voice Tracker™ II has six microphone elements and provides USB audio output as well as analog audio output at mic level through a 3.5 mm Jack. The Voice Tracker™ II is powered by USB. That power can come from the computer when the USB audio is connected, or a USB wall power supply if the analog audio is used. The Voice Tracker™ II also has embedded acoustic echo cancellation (AEC) which is useful for conferencing applications. The Voice Tracker™ II also has a mute button.
Either microphone can be used for most applications. The choice often depends on whether the customer needs the acoustic echo cancellation, small size, and USB power features of the Voice Tracker™ II.
Both microphones can be mounted on the ceiling, or on the wall in front of the room, or on a tabletop. The Voice Tracker™ I have a built-in ceiling mount. The Voice Tracker™ II comes with a separate mounting plate.
Comparison with conventional microphone and mixer approaches
In the past, microphone coverage for large areas was accomplished by combining several desktop microphones through a mixer. This approach is not only more expensive but also requires technical support from the IT department.
This approach also clutters up the tabletop. Placement of the Voice Tracker array microphones on the front wall or on the ceiling removes the clutter and minimizes wiring between the microphone and the computer.
Comparison with other array microphone approaches
Most competitive array microphones have a fixed look direction (limited field of view). They treat sound from outside that limited field of view as noise. This has some benefit, but severely restricts application for meeting recording or conferencing.
To overcome the severe disadvantage of limited field of view, several array microphone manufacturers have introduced products that combine 4-5 narrow field of view listening beams. These products have the disadvantage that they must be set up so that the listening beams point towards the places in the room where talkers are expected to be. This requires a somewhat complicated set up procedure, and can be problematic if the talker moves away from the covered area. Additionally, these products are significantly more expensive since they have several listening beams.
The largest application has been using the Voice Tracker™ array microphone for lecture capture. More than 400 schools and universities use the Voice Tracker™ array microphone.
The Voice Tracker™ array microphone has proven to be so useful for lecture recording for the following reasons:
- A single Voice Tracker™ can capture questions from the class as well as lecture from the Professor as he moves about the room. The Voice Tracker™ I has a pickup range of 30 feet and a 360° field of view.
- The Voice Tracker™ array microphone is an extremely economic solution, especially compared to the alternative of several mics and a mixer.
- The Voice Tracker™ array microphone is extremely easy to set up. Just plug it into the wall for power and connect its audio cable to the mic in jack on the PC. Support by IT personnel is seldom required. It is truly plug-and-play; no software needs to be loaded on the PC.
- The Voice Tracker™ array microphone does not suffer from cross talk which can occur with wireless microphones, especially in areas where several classrooms are close together.
- Since the Voice Tracker™ is powered by wall power, you never lose a recording because of dead batteries.
- The Voice Tracker™ is extremely reliable. Many schools leave the Voice Tracker™ on in the classroom 24/7, to simplify setup.