Sound masking levels can vary throughout a facility and should be adjusted to deliver standardized target levels for different area types. This is done to provide effective, comfortable masking under varying acoustical conditions.
- Individual Qt X controller outputs can be adjusted independently of one another to compensate for emitter and loudspeaker mounting heights and architectural conditions.
- Multiple controller outputs and multiple controllers can be employed in a virtual sounds zone.
- A Qt X virtual zone can be tied to a specific architectural space and include background music and paging signals from external audio sources if used with emitters and loudspeakers that support these functions.
Note: When setting sound masking levels, best practices call for using a sound level meter. See the "Target sound levels" topic that follows for details.
Further details can be found in the Design Considerations section of the help file.
Target sound levels
These sound levels typically provide comfortable and effective sound masking in common office environments.
|Zone Type||Measured dBA SPL|
|Private Office Zones||38-43 dBA|
|Open Area Zones||44-48 dBA|
A-weighted sound masking levels in dB SPL as measured 4ft (1.2m) above finished floor using a calibrated sound pressure level meter. A Class 1 SPL Meter / Microphone is recommended.
Qt X zone settings
If a sound level meter is not available, the levels above may be achieved in most environments by setting the Qt X sound masking volumes as follows:
|Zone Type||Qt X Zone Setting||Ceiling Height|
|Private Office Zones||-5 dB to -1 dB||All ceiling heights|
|Open Area Zones||+1 dB to +4 dB||8ft (2.4m)|
|Open Area Zones||+3 dB to +6 dB||10ft (3m)|
|Open Area Zones||+5 dB to +8 dB||12ft (3.7m)|
|Corridors||0 dB to +2 dB||All|
Note: Levels based on individual output levels set to 0 dB
Sound masking levels exceeding the previous recommendations, especially in extremely quiet environments, typically result in occupant complaints. This loss of acceptance by employees and customers can lead to staff requests to lower masking levels, ultimately reducing the effectiveness of the system. Each zone of a Qt X sound masking system should be calibrated and adjusted precisely upon installation completion by a qualified installer using calibrated measurement equipment to achieve comfortable, effective sound masking.