ARP 2600 - Page 10

4
2.126
And
the
same generating
circuit hooked
up to
the amplifier
hooked
up
to the
speaker would
cause the same back-and-forth
movement
as
in 2.124:
g
.
.
bacK
^o
s«o
-fortW
. . .
which
amounts
to getting the
sound of
a tuning
fork without hav-
ing
a tuning
fork. Or,
by
the same
principle,
the sound
of
somebody
banging on
a
garbage
can
lid without
either a garbage can lid or some-
body to bang on
it.
Or
any
sound at
all: if
you
can generate
the
right
waveform
electronically,
then you
can generate the
sound.
2.127
The
generators
we talked about
in 2.1 25 are
not imaginary;
the\ exist,
and they are
called
OSCILLATORS,
and
every
synthesizer
has
at least
a
few of
them;
a
really big
synthesizer
might have several
dozen. So
do
electronic
organs.
2.13 IF THE SHAPE
OF
THE WAVEFORM
IS MODIFIED,
SO
IS
THE SOUND,
and
vice
versa. Take
this
for the time being
as an iron-
clad
law;
there
are exceptions
but
they
don't
matter just
now.
2.1
31 Wrapping an
old
army blanket
around the garbage can
lid
muf-
fles the
sound. Carrying
it, wrapped
or unwrapped, into
a
tiled
bath-
room while
you're banging on
it changes
the sound again; and
so
on.
Anything
you
can do
mechanically
to
modify the
sound is going
to show
p
as a
modification in the
pattern of air pressure variations
and
there-
fore in
the pattern of
the changing voltages
produced
by-the
microphone.
Turn
the can
lid into a
shoebox and
kick
it
across the room—a different
waveform.
Turn it
into
a
kettledrum—another
waveform.
Spread rubber
cement over the
drumhead—
another waveform.
Fill
it
with water—
for
every pint,
another
waveform; not
by
much,
maybe,
but
still different.
2.1 32 By the
same
principle, any
modification in an
electrical
wave-
form will
modify
the sound
it makes
through
an
amplifier
and
loud-
speaker.
The
tone
controls
on a phonograph change
the
electrical
waveforms
that
pass through
them;
changing stops on an
electronic
organ or
drawbars
on
a Hammond changes
the
electrical
waveform
produced;
and EVERY
SINGLE
CONTROL
ON
A
SYNTHESIZER
has some effect
on an
electrical waveform.
u