ARP 2600 - Noise Generator: Level and Color Controls; Noise Generator Signal Characteristics

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give the gain
factor.
The
other control
input
has an
EXPONENTIAL
sensitivity. The
gain
of
the
amplifier in
response
to a control
voltage presented through
this input
will equal 10Db/Volt.
4.131
There
are
TWO SIGNAL
INPUTS
to
the
VCA.
Prewired
con-
nections
to
these
are from the VCF
and the Ring
Modulator. Either
of
these may
be automatically
disconnected by
insertion of a patch cord
into
the
proper
input
jack.
Prewired
to
the
LINEAR
control
input
is the output from the
AR
Envelope
Generator, and to
the EXPONENTIAL
control
input goes
a
prewired
connection
from the ADSR
Envelope
Generator output.
Either is
automatically disconnected by
insertion of
a
patch cord
into
the
proper
input jack.
Signal
and
control
input
impedances
are not
less
than
50Kohms.
Signal
output
impedance is 1 Kohm.
The
signal-to-noise
ratio is
greater
than 60Db
referred to
a
10V P-P
input signal.
4.2 The
NOISE GENERATOR
produces
an
audio
noise
signal of
at
least
ten
octaves
bandwidth.
Manual
controls govern LEVEL
and
COLOR.
The
LEVEL control,
at minimum, cuts
off the output
signal
completely.
At maximum,
the output
is clipped at 20V
P-P
to
produce
binary,
or
two-valued, noise.
Clipping
begins with the
level control
ap-
proximately
half
open.
The
maximum RMS
output,
if clipping is
to
occur
less
than
1%
of
the
time,
is
3V.
The
COLOR
control
is
continuously
adjustable
from WHITE
noise to
LOW-FREQUENCY
noise
output.
In the latter
case the output
falls
off at
the
rate
of
6Db/Octave;
the PINK
noise position approxi-
mates a
3Db/Octave slope.
There
is
one
signal
output.
Impedance
is
1
Kohm.
4.3 Several
of
the 2600
functions
are used
almost exclusively
for
con-
trol
purposes,
although
each of
them
may
under certain
conditions
generate
output waveforms at
audio
frequencies. They
are
not
in
any
i-EVEU
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