Dave Smith Instruments Prophet Rev2, Руководство пользователя

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30 Low Frequency Oscillators Dave Smith Instruments
Low Frequency Oscillators
The four LFOs are special-purpose oscillators that produce a frequency
that is typically below the range of human hearing (although these can
actually extend into the audio range if set to their maximum frequency).
The LFOs are typically used for periodic modulation such as vibrato
(periodic pitch modulation) and tremolo (periodic amplitude modula-
tion). They can also be used as modulation sources for any of the many
modulatable parameters in the Prophet Rev2.
The LFOs produce a variety of waveshapes, including triangle, sawtooth,
reverse sawtooth, square, and random. Though most often used for low-
frequency modulation, the Prophet Rev2 LFOs can actually function at
speeds that extend into the audible range for extreme effects.
SHAPE
Triangle
Sawtooth
Rev Saw
Square
Random
KEY SYNC
CLK SYNC FREQUENCY
AMOUNT DESTINATION
1
2
3
4
LOW FREQUENCY OSCILLATORS
The Low Frequency Oscillators
Triangle and Random waves are bipolar. That is, their waveshape is posi-
tive for half of their cycle and negative for the other half. In the case of the
triangle wave, this makes it possible to generate a natural-sounding vibrato
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frequency. Random, also known as “sample and hold,” generates a series
of random values, each held for the duration of one cycle
The square wave, sawtooth, and reverse sawtooth generate only positive values. In
the case of the square wave this makes it possible to generate natural-sounding trills.
Square Random Sawtooth Reverse
Sawtooth
Triangle
0
LFO waveshapes