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Low frequency oscillators – Dave Smith Instruments PROPHET 12 DESKTOP User Manual

Page 40

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28 Low Frequency Oscillators

Dave Smith Instruments

Low Frequency Oscillators

The Prophet 12 has four low frequency oscillators (LFOs) per voice. The LFOs

can be free-running, reset by keystrokes, or synced to the arpeggiator and MIDI

clock.

Press any of the four LFO buttons to choose an LFO for editing.

Press and briefly hold any of the LFO buttons to light all the LFO buttons and

display a single parameter for all LFOs. Turning any of the four dedicated LFO

knobs—Frequency, Amount, Shape, or Destination—will cause that parameter’s

value to be displayed for each of the four LFOs. Use the four soft knobs above

the display to adjust the individual values. Press any of the LFO buttons to return

to normal editing mode.

Frequency: 0...127

—Sets the frequency of LFO modulation routed to the

selected destination. See also “Sync.”

Amount: 0...127

—Sets the amount of LFO modulation routed to the selected

destination.

Shape: Triangle, Reverse Sawtooth, Sawtooth, Square, Pulse 1, Pulse

2, Pulse 3, Random

—The wave shape of the LFO.

Pulse 1

37.5%

Square

Sawtooth

Reverse

Sawtooth

Triangle

Pulse 2

25%

Pulse 3

12.5%

0

Random, also known as “sample and hold,” generates a series of random values,

each held for the duration of one cycle.

Triangle is bipolar. That is, it is positive for half its cycle and negative for the

other half. That makes it possible to generate a natural-sounding vibrato that goes

alternately sharp and flat in equal amounts on either side of a center frequency.

The other wave shapes and Random generate only positive values. However, any

of the LFOs can be inverted using the modulation matrix. See Modulation on

page 32 for more information.