Systems Integration Asia — February-March 2018

The Devil in the Details

Beamforming techniques exist in other industries, with antenna
arrays being rather commonly employed. Likewise, one could
argue that a microphone array looks remarkably similar to a
reversed speaker line array. And just as it is in other industries,
there are several methods to further process or interpret the signal
from the various elements in the array that result in additional
advantages, including the increased rejection of noise, tighter and
more dynamic control of the beam, or interoperability with other
technologies. Think, for example, of the potential advantages that
can be gained from knowing the direction the audio source is
coming from, derived easily by comparing the arrival time to the
various capsules. This is, indeed, very exciting as the eld
continues to evolve.

But even at its simplest form, beamforming microphones allow
designers to control the pickup pattern, usually through software,
thus affording the exibility of being able to locate microphones
in “less than ideal” positions, yet still enjoy the audio quality
usually only reserved to those located in the pick-up sweet spot.
Some microphone models allow for the creation of multiple
beams, enabling a single microphone to replace multiple
individual ones, all while providing a less intrusive and “interior
design-friendly” form factor than traditional gooseneck or lapel
microphones.

However, beamforming is still essentially static in nature. Once
designed, most beamforming microphones are rarely re-aimed,
and certainly not dynamically based on changes in the room.

Thus, traditional beamforming mics still determine where the

people speaking should be located. The ability to change a

microphone's directivity—especially in real-time—should the

arrangement in the room change or people utilising the space

prefer to move about (you know, doing crazy things like use

whiteboards or other digital tools), should not be underestimated.

How indispensable a microphone becomes when its directivity

pattern is able to automatically adjust, tracking specic signal

sources—like a person speaking as they walked around a

conferencing room to write on a whiteboard. Evolutions of this

kind make traditional beamforming much more powerful and

impressive.

Really, what's not to like about beamforming microphones today?

Martin M. Bonsoir, MInstSCE, is the International Applications Engineering

Manager at Biamp Systems, overseeing technical operations globally outside

of the Americas. With more than 23 years of industry experience, Martin's

passion for people and all things audiovisual continues to add richness and

insight to his work every day.

http://www.biamp.com

“Beamforming microphones allow

designers to control the pickup pattern,

usually through software, thus affording

the exibility of being able to locate

microphones in “less than ideal”

positions, yet still enjoy the audio

quality usually only reserved to those

located in the pick-up sweet spot”

S I A

TECH TALK

Biamp DCM-1 Beamtracking Ceiling microphone.