Creative 70EM896106000 Owners Manual - Page 98

5 - Effects Core Effects Descriptions The diagram above shows the gain curves using a Threshold at -30dB and a range of negative compression ratios. At just past 1:INFINITE, the setting of 1:-100 causes input signals approaching 0dB to be only slightly decreased below -30dB. In contrast, the compression ratio of 1:-1 causes a 2dB gain reduction for each 1dB of additional input signal level, resulting in an output signal level that is folded down over the Threshold. Create a Ducker To create a ducker, in which a background signal's level is reduced in the presence of a foreground signal, first set the Input Mode parameter to L In/R Sidechain. Then send feeds from the background signal to the left input, and from the foreground signal to the right side input. Set the Ratio parameter to -1:1 (or lower for less background reduction), and dial in a low Threshold such as -50, so any foreground signal above 50dB will cause gain reduction in the background signal. This technique works best with slow Attack and Release times - use a liberal amount of Compression Lookahead to keep the background from masking the beginning of foreground sounds. Creating a Ducker Ducker Background Signal Pan -90 (L) Stereo Strip Foreground Signal Pan +90 (R) L Gain Cell R Sidechain L Out R Input Mode The Input Mode parameter allows the compressor signal path and sidechain to be driven in common or by separate inputs. This is a feature of many compressors and is useful for a range of applications and special effects. By default, the Input Mode of the compressor is Stereo. In this mode the two independent left and right signal paths are gain controlled by a parallel sidechain path common to both inputs that contains the compressor's level detector. This single level detector works on the higher of the two input signal levels, so that signal peaks are properly compressed and no L/R image shift results from compression operations. When the Input Mode is set to L In/R Sidechain, the signal path is fed exclusively from the left channel and the sidechain is fed exclusively from the right channel. This allows dynamics control between two completely independent signals. In this mode both the compressor's left and right outputs are fed by the mono signal from the left input channel's signal path. Splitting the signal path and sidechain makes possible applications where the two signals may be completely unrelated, such as ducking. Other split-sidechain applications result from situations where a stereo input signal has had different processing applied between left and right channels. One example would be to place a stereo equalizer ahead of the compressor in order to implement a version of de-essing or "de-booming." See page 101. 98 Creative Professional