Polycom SoundStructure C16 Design Manual page 219

5. Set the output fader from the SoundStructure device to 0 as shown in the
next figure and unmute the signal generator to the loudspeaker output.
Pink noise may be heard in the room depending on the amplifier volume
settings.
6. Adjust the audio amplifier volume knob until the SPL meter, positioned
at the listener's ear position, measures approximately 75dB SPL
C-weighted.
The target level of 75dB SPL is selected because pink noise is approximately 10
to 12dB louder than human speech. Adjusting the amplifier volume so that
75dB SPL is heard in the room will ensure that when speech is played into the
room it will be at a good level for the listeners. Additional volume control can
SoundStructure
Amplifier
Installing SoundStructure Devices
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