How-To Presentation microphones 4: Ceiling microphone

Presented by: Sennheiser

#Sennheiser know-how
The TeamConnect Ceiling 2 ceiling microphone blends seamlessly into the design of modern meeting rooms.

Ceiling microphones are a modern type of microphone that is optically so unobtrusive that you almost forget the microphone during a meeting. Have you ever wondered how far away you can stay from a ceiling microphone in a meeting room and still be optimally understood? In part 4 of our series on the most important dos and don'ts for the use of microphones in business and education, we have compiled all information on ceiling microphones for you.

Ceiling microphones are becoming increasingly popular in meeting and conference rooms. Modern ceiling microphone arrays usually use beamforming technology. A microphone beam is created by the arrangement of several microphone capsules known as microphone arrays. The microphone beams of ceiling microphones not only locate and evaluate sound sources, but also suppress sources of interference. These characteristics make the technology so attractive for usage in meeting rooms. Modern ceiling microphones convince with their low installation costs and invisible cabling inside the ceiling cladding.

Flexible beamforming vs. static beamforming

Ceiling microphones with flexible beamforming detect the position of the currently speaking person in the room and focus their directional effect on this sound source in real time.

There are two different beamforming concepts for ceiling microphones used in meeting and conference rooms: static beamforming technology with defined speaker zones and automatic dynamic beamforming technology with flexible alignment. The first technology uses multiple static microphone beams simultaneously. This is not necessary with the second concept. There is only one microphone beam which automatically and flexibly aligns to the current speaker position. It is often mistakenly assumed that several beams increase the functionality of the ceiling microphone. However, the only decisive factor is how the microphone works (flexible vs. static): Since static beamforming with defined speaker zones does not result in dynamic, automatic alignment of the microphone beam to the person currently speaking, speech intelligibility decreases as soon as the speaker leaves her pre-configured microphone zone. This restricts meeting participants’ freedom of movement when, for example, they want to leave their seat at the conference table to sketch something on the whiteboard. A dynamic beam, on the other hand, allows greater flexibility during daily use and reduces installation and setup costs. The Sennheiser TeamConnect Ceiling 2 is the only ceiling microphone array with a patented combination of real-time speaker recognition and automatic, dynamic beamforming. It first detects the position of the currently speaking person in the room and then aligns its directivity to this position in real time. This gives meeting participants maximum freedom of movement in the room.

What is "automatic, dynamic beamforming" with flexible alignment?

The 28 omnidirectional microphone capsules of the TeamConnect Ceiling 2 ceiling microphone record all audio signals in the entire meeting room. Digital signal processing then selects the appropriate speaker area in real time. This means that the ceiling microphone array can determine the position of the speaker at any time – regardless of whether he or she is sitting, standing or moving around the room. The directional effect of the microphone beam is realigned within milliseconds. No spoken word is lost between the people in the meeting room and the external meeting participants who are connected via video or audio.

Conclusion

Ceiling microphones with flexible beamforming provide an unrestricted range of motion and an unobtrusive design. This ensures that the speaker does not have to align himself mentally or physically with the microphone: The speaker "forgets" the microphone. The result is a natural speech situation that makes it very easy and pleasant to follow the spoken word, especially for remote participants of telephone or video conferences. Would you like to learn more about the advantages of flexible beamforming in meeting rooms? Read our whitepaper on the differences between flexible and static beamforming!

What is beamforming?

Beamforming is a technology for the targeted shaping of sound or radio waves. Acoustic beamforming is used in ceiling microphones for the precise recording of sound sources. The beamforming of radio waves is used for example with 5G, the next generation of wireless networks. Here, the technology is used to enable transmitter systems to identify the most efficient way of transmitting data to a particular user.