Specifications

7.1 Channel strip 75
~0.7
~
0
0.2
0.4
0.6
0.8
1
0 0.2 0.4 0.6 0.8 1
Output
Control
0
0.2
0.4
0.6
0.8
1
0 0.2 0.4 0.6 0.8 1
Output
Control
0
0.2
0.4
0.6
0.8
1
0 0.2 0.4 0.6 0.8 1
Output
Control
3dB
0.5
Linear
Square root Sin/Cos
x
1−x
sqrt(1−x)
sqrt(x)
cos(x)
sin(x)
Left
Right
Left
Right
Left
Right
fig 7.10: Linear, root and sin/cos panning laws
* 0.0078745
ctlin
== 1
&&
spigot
sig~
lop~ 2
inlet midi-chan
inlet~ signal
*~ *~
outlet~ left outlet~ right
cos~
-~ 0.25
== 10
cos~
-~ 0.25
*~ 0.25
fig 7.11: MIDI panner
Combining the cosine panner patch with a
ctlin
we now have a MIDI controlled pan
unit to add to the MIDI controlled fader.
Pan information is sent on controller num-
ber 10, with 64 representing the centre po-
sition. Once again an inlet is provided to
select the MIDI channel the patch responds
to. You may like to expand this idea into
a complete MIDI fader board by adding a
mute, bus outlet and auxiliary send/return
loop. It might be a good solution to com-
bine the level control, panning, mute and
routing into a single abstraction that takes
the des ired MIDI channel and output bus as
creation arguments. Remember to use dol-
lar notation to create local variables if you
intend to override MIDI control with duplicate controls from GUI objects.
Crossfader
*~ *~
sig~ 1
-~
inlet~ signal1 inlet~ signal2 inlet~ xfade
outlet~
fig 7.12: crossfader
The opposite of a pan control, a reverse pan-
ner if you like, is a crossfader. When you
want to smoothly transfer between two sound
sources by mixing them to a common signal
path, the patch shown in Fig. 7.12 can be
used. There are three signal inlets, two of
them are signals to be mixed and one is a
control signal to set the ratio (of course a mes-
sage do main version would work equa lly well
with appropriate anti-zippe r smoothing). It can be used in the final stage o f a
reverb effects unit to set the wet/dry proportion, or in a DJ console to cross-
fade between two tunes. Just like the simple panner, the control signal is split
into two parts, a direct version and the complement with each modulating an
input signal. The output is the sum of both multipliers. This type is a linear