ARP 2600 - Exploring Prewired Patches and Experimentation; Mixer and VCF Prewired Examples; Experimental Approach Guidelines

25
small box labelled MIC
PRE-AMP.
The symbol
is
simply a diagram of
the construction
of
the
mini-jack
itself:
when
a
plug
is inserted this
is
what
happens.
THE OUTPUT FROM THE
MICROPHONE
PREAMP
IS PREWIRED
TO
THE ENVELOPE
FOLLOWER
INPUT,
AND IS
AUTOMATICALLY DISCONNECTED
WHENEVER
A
PLUG
IS
INSERTED INTO
THE JACK
INPUT TO THE
ENVELOPE
FOL-
LOWER.
3.22
For another simple
example, note that
in
the
same
row
of
jacks,
the
third
one from the right
is an input
to
the
MIXER,
and
that it is
prewired to the output from
the
VOLTAGE-CONTROLLED
FILTER
(VCF). Note again
that the
fifth of the
five AUDIO
INPUTS
to the
VCF carries a
prewired
signal from the NOISE
GENERATOR (coun-
ting across
from
left to right this is the
21 st
jack).
You
can listen to
this
input
b\
raising
the LEFT
and RIGHT
SPEAKER
ATTENUA-
TORS,
the VCF
input to the
MIXER,
and the NOISE
GEN input
attenuator to the
VCF, each about
halfway
(make
sure
that
ALL
the
other attenuators
are DOWN).
Now
experimenting
with
the t4vo hor-
izontal
control sliders at
the top
of the VCF panel
will
give
you
a
wide range of filtered sounds.
(With the
RESONANCE
CONTROL at
MAXIMUM
the VCF output
is a pure tone
independent of
any input.
In this condition
the
VCF
is
OSCILLATING
and its
output is a
SINE
WAVE.)
3.23 It
will
be
worth
your while to
experiment
thoroughly
and
sys-
tematically
with the built-in patch
connections
at
this point,
particu-
larly
if
you
are planning
to
use
the 2600 as a
live
performance instru-
ment. In section
4 we describe the
main functions
of each separate
unit in
the
2600,
and in section 5 we
give sample patches
for further
experimentation;.for the
present
we will only
give
you
a
few general
principles to keep
you
from going out
of your
skull
with complications.
3.231
EXPERIMENT
WITH ONE SIGNAL
AT A
TIME. With the
VCF,
for example,
when
you
have listened
to
everything the
filter
can
do with
a
noise
input, close that input
all
the
way
down and use the
VCO-3
SAWTOOTH
input immediately to
its
left.
Now
you
can
exper-
iment not
only
with
the
VCF
controls, but also
with
the
manual FRE-
QUENCY
controls
of
VCO-3;
and when
you
have
done
that,
experi-
ment one
by
one with the
CONTROL INPUT
signals
to
VCO-3.
s