Roland SH-201 Electronic Keyboard User Manual


 
27
Creating sounds
Creating sounds
The following diagram shows the basic process by which the SH-201 creates sounds.
fig.SH-Structure.e
The three elements of sound
There are three important elements that determine the character of a sound; the pitch, the brightness, and the volume.
On the SH-201, these three elements are specified by the following sections.
Pitch: OSC (oscillator; p. 28)
Brightness: FILTER (filter; p. 34)
Volume: AMP (amplifier; p. 38)
First, use the OSC section to specify the pitch. Next, use the FILTER section to specify the brightness. Finally, use the
AMP section to specify the volume. This is the basic procedure for creating a sound.
In actuality, the brightness of the sound is dramatically affected by the waveform generated by the OSC section, but
the process is as described above.
Time-varying change in the sound (Envelope)
The OSC, FILTER, and AMP sections can vary the pitch, brightness, and volume of the sound over time.
For example, you can make the pitch fall momentarily at the beginning of each note, or make the volume of each note
gradually increase.
The way in which some aspect of a note changes over time is called the “envelope.” The envelope is specified by the
following sections.
Pitch:
PITCH ENV
(pitch envelope; p. 31)
Brightness:
FILTER ENV
(filter envelope; p. 37)
Volume:
AMP ENV
(amp envelope; p. 38)
Cyclic change in the sound (Modulation)
The OSC, FILTER, and AMP sections can also be controlled by an LFO (Low Frequency Oscillator; p. 40) to cyclically
vary aspects of the sound such as pitch (producing vibrato) or volume (producing tremolo).
Cyclic change applied to the pitch, tone, or volume in this way is called “modulation.”
The SH-201 has two LFO units, allowing you to simultaneously apply modulation of differing speeds and
waveforms.
How sounds are created
FILTER ENV
AMP ENV
Control signalsAudio signals
Varies the brightness
as the sound begins
or ends
LFO 2
Modulates the pitch,
the brightness, or
the volume
LFO 1
Modulates the pitch,
the brightness, or
the volume
PITCH ENV
Varies the pitch
at which the
sound begins
Specifies how the
sound begins and
ends
MIX/MOD
Mixes
waveforms
FILTER
Specifies the
brightness of
the sound
AMP
Specifies the
loudness of
the sound
EFFECTS
Adds depth or
spaciousness
OSC 1
Generates the
waveform and
specifies the pitch
OSC 2
Generates the
waveform and
specifies the pitch
A patch suitable as a starting point for creating sound “from scratch” is provided at the end of preset group
bank D. Use this patch as desired.
SH-201_r_e.book 27 ページ 2006年4月27日 木曜日 午前11時28分