Page 1, 2, 3, 4, 5, 6
The first effect in the MixMaster’s chain is a low-threshold stereo expander optimized for suppressing audible noise at the beginning of a mix or after a fade-out. The expander has two continuously variable controls: Threshold and Release. Threshold sets the triggering level and ranges from –60 to –20 dB. Release governs the amount of time (from 0.5 to 6 seconds) it takes for the expander to fade to silence. The optical sensor used in the circuit provides smooth fades and lower noise and distortion than VCA circuits. The expander has a bypass switch and an LED ladder meter that indicates the gain reduction in 3 dB increments between 0 and –15 dB, and 5 dB increments from –15 to –30 dB.
 |
|
Fig.
2: In addition to the main XLR and 1/4-inch inputs, the MixMaster
includes a pair of balanced auxiliary Direct Inputs (click for larger
image).
|
Release governs the amount of time it takes for a compressed signal to return to its uncompressed state once it drops below the threshold. Release has four preset values (0.2, 0.4, 0.8, and 1.6 seconds) and two automatic settings labeled PDF (program-dependent fast) and PDS (program-dependent slow). Those apply varying release times to the compressed audio based on the transient characteristics of the signals occurring above the threshold. The final knob is a Make Up Gain control, which compensates for any gain reduction due to compression.
When the Lock switch is on, the compressor disregards the mix’s frequency content. When the Lock switch is off, the compressor becomes frequency dependent, splitting the audio into three bands and bringing additional controls into play. Separate Low Frequency (LF) and High Frequency (HF) trim pots give you independent control over the level of the bass and treble frequencies, respectively. For example, a dominant kick drum’s boom—which may trigger undue compression effects or pumping in a conventional compressor—can be trimmed so the compressor reacts less to the mix’s bass range. Both controls are zero-detented and continuously variable from –10 to +10 dB.
There is no trim control for the mid-frequency compression band and no control over the crossover frequency between the high and mid bands. But the MixMaster does offer a useful low-end option with the Slope switch, which toggles the crossover point between the low and mid band to 100 or 200 Hz. In the 100 Hz position, a circuit similar to that used in the Platinum ComPounder boosts the bass below the crossover point.
Red LEDs indicate extreme compression levels (–12 dB and beyond) with lower gain-reduction values indicated in orange. A red LED above the Make Up Gain control indicates overload or clipping resulting from excessive gain boosting. The overload-threshold value is not provided in the manual, but in testing, that LED lit up when output levels approached –2 dB.
__
Reprinted with permission from
Magazine, February, 2001© 2000, Intertec Publishing, A Primedia Company All Rights Reserved
[an error occurred while processing this directive]
