20 9710 VCA
000216
THE PANEL CONTROLS
You got to know the panel controls pretty well during testing. Here's a different perspective on
what they do.
VCAs
Left input. 5V p-p nominal max input. The arrow
is a reminder that the Noise source normals to this
input. The normal is overridden by an external input.
Right input. 5V p-p nominal max input. May be
audio signal or Control Voltage.
A input. 5V p-p nominal max input. The mix of L
and R input is normalled to this input and overridden
when an external input is applied.
Left and Right Control Voltage inputs. The symbol from CV
L
to CV
R
is a
reminder that these inputs are normalized with an inverter between them so that
an increasing Control Voltage applied to CV
L
increases the gain of the Left VCA
while decreasing the gain of the Right resulting in a panning or morphing between the Left and
Right inputs. An external CV applied to CV
R
interrupts the inverter and increasing CVs
increase gain.
A Control Voltage input. The arrow reminds that this input normals to the
ADSR output. You'll have to remember on your own that there's a 10dB/V
exponential converter as part of this connection. External inputs interrupt the normal and the
expo converter. External signals may be up to +/- 10V p-p for VCA or Balanced Modulator.
Left output. The output of the Left VCA. It's not shown on the graphics but a
plug inserted in this jack interrupts its normal connection to the L+R output and
also the A input which allows the noise source to isolated and used alone.
Right output. The output of the Right VCA.
Left + Right mix output. The mix of the L VCA and R VCA outputs as set by the
Pan control and other CVs on the CV
L
and CV
R
inputs. Because of the passive
mixing at this output it is -6dBV relative to either of the direct outputs or the nominal peak A
VCA output.
A output. The output of the A VCA. Like most VCAs the 9710 sections are
actually attenuators that have unity gain when CVs are their nominal max (10V).
PAN Control - Sets the relative gain of the L and R VCAs. The linear control voltage response
of the L and R VCAs means that for equal L and R inputs, Peak signal level at either the L+R
or A outputs remains constant during panning.
