Moog stage ii 사용자 가이드
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LP Stage II User’s Manual - Appendices
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LP Stage II User’s Manual - Glossary
Glossary
Here are a few key terms that cover the basics of sound generation as used in the Little Phatty synthesizer.
ADSR – Abbreviation for Attack, Decay, Sustain and Release, the four stages of an envelope control voltage
.
Amplitude – The strength of a sound’s vibration measured in Decibels (dB). Amplitude corresponds to the
musical term Loudness.
Continuous Controller (CC) – A type of MIDI message used to transmit control commands. These com-
mands are digital control signals for parameters such as volume, vibrato and panning.
Control Voltage – Control voltages (also called CVs) are used in analog synthesizers to affect changes in the
sound. In the case of pitch, pressing a key on the keyboard sends a control voltage that determines the
pitch of the oscillators. The keyboard CV is set to produce an equal tempered scale. As you play up the
keyboard, the CV is raised and the pitch increases. The pitch can also be affected by other CV sources,
like an LFO, often used to produce vibrato. Other major synthesizer components that respond to CV’s
include the filter (the higher the CV, the higher the filter cutoff frequency) and the amplifier (the higher
the CV, the higher the gain, or volume).
pitch of the oscillators. The keyboard CV is set to produce an equal tempered scale. As you play up the
keyboard, the CV is raised and the pitch increases. The pitch can also be affected by other CV sources,
like an LFO, often used to produce vibrato. Other major synthesizer components that respond to CV’s
include the filter (the higher the CV, the higher the filter cutoff frequency) and the amplifier (the higher
the CV, the higher the gain, or volume).
Envelope – An envelope describes the contours that affect the characteristics of a sound (pitch, tone and
volume) over time. For example, when a string is plucked, its amplitude is suddenly very loud, but then
dies out gradually. This describes the Volume envelope of the sound. We observe that the initial part of
the plucked sound is very bright, but then the brightness fades away. This describes the Tonal envelope
contour. We also hear the frequency of the sound go slightly higher when the string is plucked, and then
drop slightly as the note fades. This is the pitch envelope contour. A synthesizer can create these kinds
of changes by applying electrically generated envelopes to oscillators (affecting pitch), filters (affecting
tone) and amplifiers (affecting volume).
dies out gradually. This describes the Volume envelope of the sound. We observe that the initial part of
the plucked sound is very bright, but then the brightness fades away. This describes the Tonal envelope
contour. We also hear the frequency of the sound go slightly higher when the string is plucked, and then
drop slightly as the note fades. This is the pitch envelope contour. A synthesizer can create these kinds
of changes by applying electrically generated envelopes to oscillators (affecting pitch), filters (affecting
tone) and amplifiers (affecting volume).
Envelope Generator – A circuit that generates an envelope signal. The envelope generator creates a time-
varying signal that can be applied to any voltage-controlled circuit. The Envelope Generators in the
Little Phatty have four adjustable segments: Attack, Decay, Sustain and Release, also sometimes referred
to as ADSR. The Attack, Decay and Release segments are specified as time parameters, while the
Sustain segment is a simply a level setting. Attack specifies the onset time of the envelope. For example,
the sound of a plucked string starts suddenly, meaning its volume envelope has a fast attack time. Decay
specifies how quickly the onset of the envelope fades into the sustained portion. Sustain is the level at
which the envelope sustains after the initial transient (the attack and decay portion). Finally, Release de-
termines how long the envelope takes to fade away. An Envelope Generator uses a trigger to start and
stop the ADSR envelope. This trigger is called a gate signal, and it’s produced whenever a key is pressed
on the keyboard. The gate signal turns on and stays on as long as a key is held down. When the key
is released, the gate signal turns off. When the gate is on, the Envelope Generator is triggered and the
envelope signal moves through the Attack and Decay segments and settles at the Sustain level as long as
the gate signal is on. When the gate goes off, the release segment of the envelope begins. A new gate
signal retriggers the Envelope Generator.
Little Phatty have four adjustable segments: Attack, Decay, Sustain and Release, also sometimes referred
to as ADSR. The Attack, Decay and Release segments are specified as time parameters, while the
Sustain segment is a simply a level setting. Attack specifies the onset time of the envelope. For example,
the sound of a plucked string starts suddenly, meaning its volume envelope has a fast attack time. Decay
specifies how quickly the onset of the envelope fades into the sustained portion. Sustain is the level at
which the envelope sustains after the initial transient (the attack and decay portion). Finally, Release de-
termines how long the envelope takes to fade away. An Envelope Generator uses a trigger to start and
stop the ADSR envelope. This trigger is called a gate signal, and it’s produced whenever a key is pressed
on the keyboard. The gate signal turns on and stays on as long as a key is held down. When the key
is released, the gate signal turns off. When the gate is on, the Envelope Generator is triggered and the
envelope signal moves through the Attack and Decay segments and settles at the Sustain level as long as
the gate signal is on. When the gate goes off, the release segment of the envelope begins. A new gate
signal retriggers the Envelope Generator.