Yamaha CS-80 Instruction Manual page 44

Hide thumbs

Advertisement

SECTION
V - UNDERSTANDING SYNTHESISERS
4
i
40
This section
first
deals
with
several basic
conceptual
questions
about
synthesizers.
While
we
have
distilled
the
information
as
much
as
possible,
some
topics
have
philosophical or
complex
origins
that
do
not
lend
them-
selves
to simple explanations.
The
balance of the
section
provides an
overview
of
how
the
CS-80
operates,
much
of
which
can
also
apply
to
other
synthesizers.
What
is
a
Synthesizer
A
synthesizer
is
an audio processor that has
a
built-
in
sound
generator
(oscillator),
and
that
alters
the
envelope
of the
sound
with
voltage controlled
circuitry.
Synthesizers can
produce
familiar
sounds and
serve
as
musical instruments,
or
they can
create
many
unique
sounds and
effects of their
own.
The
synthesizer oper-
ates
by
creating
each
basic
element
of
sound and
then
providing
you
with separate controls
for
each element.
You
don't have
to use
all
the
many
controls
on
the synthesizer
to create
a
complete
sound.
In
fact,
often only
a
handful
of
the
available
controls
need
be
used,
depending on
the
sound you
wish
to achieve.
The
Difference
Between
Synthesizers
&
Electric
Organs
An
electric
organ
offers
a
wide
variety of preset
sounds
at
the
touch
of
a
finger.
Synthesizers usually
offer
no
presets,
or very
few
of
them,
instead pro-
viding
an
infinite
variety of adjustable
sounds.
The
CS-50,
CS-60 and CS-80
offer
many
presets
and
infinitely
adjustable
sounds
as well.
Organs
utilize
different
means
to
generate
sound
than
do
synthesizers.
Because
of
this,
most
organs
are
polyphonic,
meaning
that
you
can
play
many
notes
simultaneously,
whereas
most
conventional
synthesizers
allow
you
to play
only
one
note
at
a
time.
The
CS-
Synthesizers,
however, incorporate
additional
circuitry
that allows
you
to play
several
notes
at
a
time
(4
on
the
CS-50 and
8
on
the
CS-60 and
CS-80).
Why
Use
a
Synthesizer
Many
of
the
sounds
that
can be created with
a
synthesizer
would
be
either
Impossible
or highly
impractical to create
with acoustic instruments.
Also,
the synthesizer
can
give
you
common
acoustical
sounds
with
much
greater
convenience
than
would
otherwise be
possible.
For
instance,
you
can
adjust
the controls to "stretch"
a
common
instrument,
like
gradually
transforming
a
piccolo to
a
Bass
flute,
or
even
to
a
20' long
flute.
If
there
were
such
a
thing.
Similarly,
the synthesizer allows
Instant or gradual
transitions
from
the
sound
of
one instrument
to
another.
The
Elements
of
a
Synthesizer
One
section,
the
VCO,
establishes the pitch or
frequency
of the note,
as
well
as
the basic
tone
(timbre).
Another
section,
the
VCF,
shapes the tone
or
emphasizes
portions of
it.
Another
section,
the
VGA,
affects
the
loudness
of the notes. Either the
VCF,
the
VCA,
or
both
may
be used
to
"turn
on" and
"turn
off" the
sound
in
a
controlled
pattern,
forming
the
notes
as
you
play the
keyboard.
The
control that
forms
the
notes
is
provided by Envelope Generators
(EG),
one
for
the
VCA
and one
for the
VCF. The
synthesizer
also
houses
many
other functions to
modify
the
basic
sounds
for
a
variety of
effects.
Yamaha
CS-series synthesizers,
because they
are
polyphonic,
are
actually
equipped
with
several
VCO's,
VCF's,
VGA's and
EC's:
16
sets
on
the
GS-80
for
creating
each
of the
8
notes times 2 voices that
can
be
played simultaneously.
Why
Voltage Controlled
Circuits are
used
in
Synthesizers
& How
They
Work
You
can
set
up
voltage controlled
circuits
to
make
changes
automatically.
Suppose you
have
a
sub
oscillator
that
produces
a
continuously changing
voltage
(AG), such
as
the
slow
sine
wave from
the
CS-80's
Sub
Oscillator.
If
you
apply
that voltage to
the control input of
a
Voltage Controlled
Amplifier,
the
sound
passing
through
that amplifier
will
go
up
and
down
in
level— creating
a
tremolo
effect.
(This
is
exactly
what happens
when
you
move down
the
VCA
lever
In
the
Sub
OscillatorSection.)
At
this
point
you
are listening to
one
sound
source
that
is
being
modulated
or controlled
by something
else, a
sine
wave.
If
you
Increase the
SPEED
of the
Sub
Oscillator,
the rapid
changes
in
control voltage
will
make
the
sound
level
change
so
fast
that beating occurs,
producing secondary
tones.
You
can
also
adjust
a
voltage controlled
circuit
manually.
If
you
wish,
just
like
any
conventionally
controlled
circuit.
For example,
you might
achieve
the
same
slow-speed
tremolo
effect
by continuously
mov-
ing
a
Volume
control
up and down,
If
you
had
the
fingers free
to
do
it.
However,
you
could not
possibly
move
that
volume
control
fast
enough
or
smoothly
enough
by
hand
to
produce secondary
tones.
Thus,
voltage controlled
circuits
enable
you
to
do
things
that
could not
be
readily
accomplished
with purely
manually
controlled
circuits.
Amplifiers
(VGA's)
are
not
the
only
voltage
con-
trolled circuits
in a
synthesizer;
filters
and
oscillators
may
also
be voltage controlled.
In
all
Instances,
the
amount
of
change
In
the
sound
is
proportional
to the
voltage applied to the control
circuit.
The same
sine-
wave
voltage
from
the
Sub
Oscillator that
created
tremolo
in
the
VCA
when
applied to the control
in-
put
of
a
VCF
would
create
wah-wah,
or
when
applied
to
a
VCO
would
create vibrato.
It
is
not
at
all
important
for
a
player
to
understand
about
voltages
and
control
circuits
to
program and
play
the
GS-80.
When
you
set
the controls
and
levers
so the
sound
Is
"right,"
you
are
probably
adjusting control
voltages.

Advertisement

loading

  Related Manuals for Yamaha CS-80

Table of Contents