Roland U-20 Owner's Manual page 48

BEFORE
YOU
CREATE
YOUR
OWN
SOUNDS
Before
you
begin
creating your
own
sounds, read
this section
to
learn
how
the sound
generator
in the
U-20
creates sounds.
1.
Tones
Here
we
will
explain the features
of the U-20's
RS-PCM
sound
generator.
•RS-PCM
Sound Generators
RS-PCM
stands for
ReSynthesized
Pulse
Code Modulation.
PCM
is
a
method
of storing a
sound
waveform
as a
digital
sound
recording.
However,
simply recording
and
playing
back
the sound
of
an
instrxmient
does not always give
musically appropriate
results.
RS-PCM
uses Roland's unique technology
to
analyze,
modify,
and
"resynthesize" the
PCM
recorded instrumental
sound. This
results in a
realistic
sound
that
can be
controlled
in musically appropriate ways.
The
basic
sound
of the
RS-PCM
sound
generator
is
the
"Tone".
Internal
memory
contains
128 Tones.
PCM
cards
(sound Ubrary cards
(SN-UUO
series)
for the U-110)
can
also
be
used,
providing even more
soxmds.
The
U-20 does not simply use the Tones
as
they
are,
but
allows
you
to
modify
the
way
in
which volume and
pitch change, or
how
vibrato
is
applied.
This
lets
you
easily create
your
own
soimds.
#Tvpes
of
Tone and Simultaneous Polyphony
The
U-20 can produce
up
to
30 sounds
(voices) at once,
but
this will
depend on
the type
of
Tones
being
used.
Tones which
consist of
a
single voice
can
play
up
to
30
notes.
Tones which
consist of
two
voices
can play
up
to
15
notes, (cr
Refer
to
page
59,
"Tone
select".)
•Pitch Range
Tones have an upper
limit
beyond which they cannot
produce
sound.
Each
acoustic
instrument has a
different
sound-producing
range,
and
the soimd-producing ranges
of
the U-20's
sounds
are
based on
these ranges.
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