Casio CZ-5000 - Understanding Envelopes

ee
re 2} Envelopes
Eres)
— —— Other Factors Determining a Sound
er to
ocess
|
e
fre-
Besides
the
three
basic
elements
of
sound
already
explained,
pitch,
sound
volume
and
timbre,
there
is
another
C
are
important
factor
which
determines
a
sound.
This
is
the
variation
of
the
sound
over
time.
More
precisely,
roach
it
is
the
variation
of
each
of
the
three
elements
over
time
from
the
beginning
of
the
sound
up
to
the
point
»5
are
in
time
where
it
disappears
completely.
!f
a
violin
is
played
with
a
bow,
for
instance,
the
sound
volume
usually
basic
increases
gradually
while
the
timbre
and
pitch
also
change
slightly.
These
changes
over
time
are
what
deter-
mines the characteristic timbre of a violin. On the other hand, if the sound of a piano were to continue with-
Vaves
out
decaying,
it
would
be
very
difficult
to
distinguish
it
from
the
the
sound
of
a
flute.
These
variations
over
})
are
time
are
called
envelopes.
Envelopes
expressed
graphically
such
as
those
in
the
diagrams
below
are
called
onics envelope curves.
your
Oni Envelope Curves of Various Instruments (Sound Volume)
,
oe
Piano
Flute
Violin
Volume
|
|
Volume
Volume
—
:
|
Time
Time
ies
| The change of volume over time can also be called an envelope.
-— Remember _)
The changes over time of pitch, volume and timbre are called envelopes. Envelopes are among the |
| | most important factors determining a sound.
th
;
|
a
<)
Basic
Principles
of
Analog
Synthesizer
Structure
When peopie talk about synthesizers, you will often hear expressions such as VCO and VCF. Many who
“e- have heard such difficult words will therefore find it difficult to approach synthesizers, believing they are
re too complicated. Actually, though, synthesizers are not that difficult to understand at all.
iv Analog synthesizers in general consist of various blocks which correspond to the three major elements of
Iv sound and the envelopes explained above.
e VCO (Voltage Controlled Oscillator}
This circuit corresponds to determines the pitch of a sound by controlling voltage. This block is also used
—, to create Dasic waveforms such as saw-tooth waves or square waves.
ye
3
e
VCF
(Voitage
Controlled
Filter)
This circuit alters the timbre by accentuating or filtering out certain harmonics of the waveforms created
by the VCO. The VCF might be called the most important part of an analog synthesizer.
®
(03)
e