E-MU 1212M PCIe - Manual (Page 97)

5 - Effects
Core Effects Descriptions
E-MU PCIe Digital Audio Systems 97
Max Compression
This parameter is used to limit the amount of gain reduction that the compressor can
apply. The limit is set as a maximum number of dB of gain reduction, from 3dB to
UNLIMITED.
0dB
-30dB
-80dB
Threshold: -30dB
Max. Compression
Max. Comp. = 6dB
Max. Comp. = 15dB
Max. Comp. = 24dB
Ratio = 4:1
This feature emulates the phenomenon of the compression “tail” found in the gain
curves of some classic analog compressor/limiters. The phenomenon results from the
inability of these devices to apply more than a certain amount of compression to the
input signal. When the device “runs out” of enough gain reduction to compress a very
high level signal, it resumes a 1:1 gain curve again. This “deficiency” has the
unexpected sonic benefit of restoring some dynamics to the compressed signal - but
only on the highest input peaks - thus adding some “life” back into otherwise over-
compressed signals.
Note: You may need
to use the Gain parameter
to keep these restored
peaks from clipping the
compressor output since
Auto Makeup gain doesn't
automatically take the
compressor tail into
account.
Unlike analog compressors, the Max Compression parameter allows you to adjust the
amount of gain reduction before the compressor returns to a 1:1 gain curve. The
diagram shows three settings of the Max Compression parameter; the compressor
“gives up” and returns to 1:1 after 6, 15 and 24dB of compression have been
exhausted, respectively.
The parameter is most useful at higher compression ratios, allowing the gain curve to
be carefully tailored to the dynamics of the signal as well as the Threshold and Ratio
parameters. The limit set by the Max Compression parameter does not apply to gain
reduction performed in the Soft Knee region of the gain curve.
0dB
-30dB
-80dB
Threshold: -30dB
Neg. Comp: Enabled
-10:1
-5:1
-3:1
-2:1
-1.5:1
-1:1
Ratio
Neg Compression
When the Neg Compression
parameter is Enabled, the range
of compression values available
to the Ratio parameter extends
beyond INFINITE to encompass
negative compression ratios from
1:-100 down to 1:-1. Using
negative compression ratios
results in an output signal that
actually gets quieter as the input
signal rises above the threshold.
This action can be useful for
applications like ducking and for
other special effects.