What is TruVoicelift?
29 September 2021
How the voice lift system “TruVoicelift” for TeamConnect Ceiling 2 brings speech intelligibility to the entire meeting room
TruVoicelift is Sennheiser's interpretation of the voice lift function as applied to the TeamConnect Ceiling 2 (TCC 2) ceiling microphone solution. A voice lift system is used whenever it is necessary to ensure that the person speaking via a microphone is clearly understood throughout the room. The aim is therefore to achieve good speech intelligibility. The primary objective is to bridge the sound level loss over the distance between the speaker and the listener: the further away a listener is from the speaker, the higher the sound level loss and the softer the speaker’s voice sounds to him.
How does TruVoicelift work?
Sennheiser’s TruVoicelift algorithm, which can be activated and configured, has two features that prevent the occurrence of feedback: the Frequency Shifter and the Feedback Prevent Mute function. In addition, the Noise Gate function prevents unwanted background noise from being picked up by the microphone during pauses in speech. In addition, the Advanced Exclusion Zones ensure that the loudspeakers in the room are not detected as a speech source and thus prevent early feedback in the system.
- Frequency Shifter: The algorithm constantly adjusts the audio signal for optimal feedback rejection by changing the frequency.
- Feedback Prevent Mute: The built-in function prevents potential feedback loops. When a certain threshold is reached, the microphone is muted for a few seconds to prevent a feedback loop. Threshold and mute time can be configured individually.
- Noise Gate: To prevent TCC 2 from picking up unwanted background noise when the microphone beam is not detecting an active speaker, the noise gate can be set to a specific decibel threshold. Then only audio signals above this defined level will activate the microphone.
In which rooms are voice lift systems used?
A voice lift system is used in larger rooms such as:
- Larger training rooms or classrooms
- Lecture halls in universities
- Larger meeting rooms
- Multipurpose rooms used for presentations
The decisive factor here is not so much the size of the room as the distance between the speaker and the listener. Assuming an averagely loud voice, the use of a voice lift system can make sense from a distance of 8 to 10 meters.
Differences of a voice lift system compared to classic PA systems
A voice lift system amplifies a person’s voice in one part of the room only enough so that people in other parts of the room can hear it clearly. It usually increases the speech level in the room by 3 to a maximum of 6 decibels. For a public address system (PA), a much higher level is required, which can only be achieved with close-talking microphones such as headsets, lavaliers or hand-held microphones.
A high level of gain before feedback is important for increasing the speech level. Gain before feedback is a measurement that indicates how high the input signal can be levelled before audio feedback from the microphone occurs. With TruVoicelift, a higher level of gain before feedback can be achieved than with other systems, which means that the speech transmission is significantly louder than in other applications. Depending on the room conditions and size, the overall gain before feedback is +6 to +9dB. This allows the customer to significantly improve speech amplification in meeting rooms.
Dive into the exciting world of new features of the TeamConnect Ceiling 2 microphone!
Want to learn more about the new features of the ceiling microphone? We have compiled an overview of all available blog posts for you here:
- Go directly to the blog post “How to configure your meetings in a more customized way with Advanced Exclusion Zones”
- Go directly to the blog post “How to use the Priority Zone to create targeted focus in your meetings”
- Go directly to the blog post “How the Frequency Shifter enables optimal feedback suppression in your meetings”
- Go directly to the blog post “How Integrated Feedback Prevent Mute Protects Your Meetings from Unwanted Feedback”
- Go directly to the blog post “How Noise Gate Prevents Distracting Noise in Your Meetings”