Software Instruction Manual

IQ–MSD Turbo 1.4 Advanced IQ System Software
Page 161
Threshold: The Threshold control determines at what ambient sound level the AMB function will begin to
operate. It is the sound pressure level (SPL) of the ambient sensing input (Input 6). When the signal level of Input
6 exceeds the Threshold setting, the AMB function begins to increase the gain of Channel 1 at the rate dictated by
the Expansion Ratio control.
Ambient Offset: The Ambient Offset is like a fixed insertion loss. It is the level
below the Gate function Max
Gain settings to which the Channel 1 gain will be set
until the ambience level exceeds the Threshold setting. As the
ambience level increases above the Threshold setting, the Channel 1 gain will be increased above the Ambient
Offset according to the Expansion Ratio setting. The Max Gain settings always limit the maximum possible gain
which any input can receive.
Inputs whose net gain is forced below the Ambient Offset by the other functions are ignored by the AMB function.
This prevents the AMB function from attempting to increase the gain of inputs whose gates have been closed.
The following list shows the possible settings for each AMB function control. Note: All dB settings are dBu.
Ambience: On/Off
Attack Time: 0.2, 0.4, 0.6, 0.8, 1, 1.5, 2, 3, 4, 6, 8, 10, 12, 15, 20, 30 seconds
Decay Time: 0.2, 0.4, 0.6, 0.8, 1, 1.5, 2, 3, 4, 6, 8, 10, 12, 15, 20, 30 seconds
Expansion Ratio: 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 4:1, 5:1
Guard Band: 0, 1, 2, 3, 4, 5 dB
Threshold: Off; –99½ dB to +25 dB in ½ dB steps
Ambient Offset: 0 to 40 dB in ½ dB steps