Aurora Audio GTQC - Manual (Page 5)

depending on whether the red FET switch is selected.
If the Combined switch is pressed, relays reconfigure the internal circuit paths so that both control
elements are in circuit. The signal passes first through the opto path and is then applied to the FET path
for additional control. As both paths are unity gain before compression, there will be little difference in
compression until both sections start working hard and then it will be seen to compress as much as
another 6dB. (i.e double the single control element value).
The Combined mode's main function is not just to squash the living daylights out of a signal but rather to
provide the user with a third option of sound signature. When the Combined switch is used, try having the
Threshold and Ratio controls at minimum and then gently rotating the Threshold until the gain reduction
meter indicates that the side chain is beginning to work. Listen to the color of the sound at this point and
the effect on that sound by adjusting the other controls. It's a very useful feature!
Stereo Link Off/On (Yellow Switch) :- (Assumes that the GTQC is linked to another GTQC) .... If not
selected the compressor channel works completely independently and can be assigned to different circuit
paths with different degrees of compression.
If the Stereo button is pressed the two GTQC compressor sections will work together as a stereo unit (i.e.
as a stereo bus compressor) with whichever channel has the most side chain voltage (i.e. the most
compression at that instant in time) taking control over both channels and providing identical amounts of
compression.
The control will pass seamlessly from one channel to the next depending on which of the two is working
hardest and, as a consequence, the stereo image should not drift from center.
NB. For the stereo link to function properly, both compressors should have the same control
element selected (i.e opto/FET/combined) and the bypass and sidechains should both be switched to
the “on” position.
← Switch Source to Preamp Output (Red Switch) :- The compressor normally works independently
from the microphone amplifier/equalizer but, if the red switch is pressed, the compressor's input is
sourced from the pre-amplifier output creating a complete channel strip function. The pre-amplifier output
XLR is unaffected and can be used as a pre-compressed output.
5. Compressor Specifications
Input Impedance = 10Kohm balanced and floating, transformer coupled.
Output Impedance = <75ohm balanced and floating, transformer coupled
Output drive capability = +26dBu into any load of 600 ohms and above
Frequency response = 20Hz to 20KHz ± 1dB
Total Harmonic Distortion = < 0.1% @ +20dBu O/P @ 1KHz
Noise = < -75dB filtered 20Hz to 20KHz
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