User manual

Drive Control
Descripon
MODEL 1 incorporates a unique feature on every input, the Drive control. This control
allows the user to adjust the level at which the channel pre-amplier clips the input signal,
thus creang harmonic distoron as an eect. This is achieved by adjusng the conducon
threshold of circuitry in the feedback loop of the pre-amplier by rotang the “Drive”
control. The Drive control incorporates an LED which illuminates the transparent sha to
indicate when the clip threshold has been reached.
The Drive control and Trim work in combinaon with each other and the amount of
distoron is dependant on several factors; the level of the input signal, the posion of the
Trim and the posion of the Drive. With the Drive control fully counter clockwise the
distoron circuitry is disabled and the channel can be run cleanly well beyond the level at
which the Peak LED lights. With the control fully clockwise, any signal level above
approximately -4dBu will trigger the distoron circuits.
The Drive control is also linked to the channel fader VCA and automacally adds make-up
gain at extreme clip levels, therefore it is normal behaviour for there to be a discrepancy
between the Channel and Master buss metering signal levels. Post –fader level also
inuences brightness of the Drive LED illuminaon.
Fixed level Drive circuitry is built into the Return input pre-ampliers, and can be triggered
by driving the Return signal level beyond that which lights the Peak LEDs
9
Driving the signal level higher results in greater
compression of the signal peaks.
This trace shows the signal level at the clip threshold
with the peaks being slightly rounded or “so clipped”
which will add warmth and strong 2nd harmonics.
This trace shows two signals, one running through the
drive circuit and one not. As the clip threshold has not
been reached, both signals are idencal.
This shows the signal very heavily clipped, virtually to a
square wave.
PRE-AMP
Clip Level
Signal Level