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HF-100 Users Guide
louder than -50dB the output audio will begin to be compressed or lowered. For this example,
there is a second threshold at -20dB in which the output audio will be compressed even more.
This second threshold is o en used to reduce clipping.
Compression Ra o 0
Compression Ra o 0 is the slope of the line to the le of Threshold 1. This ra o de
fi
nes what is
to happen to the audio gain when the audio levels are lower than Threshold 1. A ra o of 1 will
be parallel to the Iden y Line.
Compression Ra o 1
Compression Ra o 1 is the slope of the line between the Threshold 1 and Threshold 2 range.
This ra o de
fi
nes what is to happen to the gain when the audio levels are within this range.
Compression Ra o 2
Compression Ra o 2 is the slope of the line a er Threshold 2. This ra o de
fi
nes what is to
happen to the gain when the audio levels exceed Threshold 2. O en Threshold 2 and this ra o
se ng act as a limiter to remove the chance of clipping or overdriving an amp and/or speaker.
O
ff
set Region 1
This value is calculated as a func on of other se ngs.
O
ff
set Region 2
This se ng is actually very important. This value is the dB o
ff
set along the Threshold 2 ver cal
line from the black iden ty line. In the example above, at the Threshold 2 audio level, the
output will be the equal to the input dB minus this o
ff
set. From a graphical standpoint, the
Threshold 2 in
fl
ec on point will occur exactly -16dB.
O
ff
set Region 2 modi
fi
es the output gain for the en re range of possible audio input levels.
Satura on Zones
. Keep the blue line out of these areas. This is a visual representa on of where
you will be exceeding the capabili es of the DSP audio chip. Clipping and other unwanted
ar facts will occur.
Energy
The DRC processing block is constantly sampling the incoming audio stream to determine its
amplitude. Energy is the e
ff
ec ve look-back me “window” over which the average amplitude
is calculated. The value of that average amplitude is used to trigger the DRC compression or
expansion ac vity.
A ack & Decay
A ack and Decay de
fi
ne the transi on me of changes in the audio gain. See above graphic.
If the incoming audio levels are intended to be compressed or lowered, the a ack me
determines how much me will pass before the incoming gain is lowered. Conversely, if the
incoming audio levels are to be expanded or raised, the decay me determines the me it will
take to increase the gain and the a ack me determines how fast it will take for the audio levels
to return to nominal levels.
WARNING: Keep blue lines out of Satura on areas. Audio at these amplitudes could damage
this product.
