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# lfo

lfo -- A low frequency oscillator of various shapes.

## Description

A low frequency oscillator of various shapes.

## Syntax

kr lfo kamp, kcps [, itype]

ar lfo kamp, kcps [, itype]

## Initialization

itype (optional, default=0) -- determine the waveform of the oscillator. Default is 0.

- itype = 0 - sine

- itype = 1 - triangles

- itype = 2 - square (bipolar)

- itype = 3 - square (unipolar)

- itype = 4 - saw-tooth

- itype = 5 - saw-tooth(down)

The sine wave is implemented as a 4096 table and linear interpolation. The others are calculated.

## Performance

kamp -- amplitude of output

kcps -- frequency of oscillator

## Examples

Here is an example of the lfo opcode. It uses the files lfo.orc and lfo.sco.

Example 1. Example of the lfo opcode.

    /* lfo.orc */
    ; Initialize the global variables.
    sr = 44100
    kr = 4410
    ksmps = 10
    nchnls = 1

    ; Instrument #1.
    instr 1
      kamp = 10
      kcps = 5
      itype = 4

      k1 lfo kamp, kcps, itype
      ar oscil p4, p5+k1, 1
      out ar
    endin
    /* lfo.orc */

    /* lfo.sco */
    ; Table #1: an ordinary sine wave.
    f 1 0 32768 10 1

    ; p4 = amplitude of the output signal.
    ; p5 = frequency (in cycles per second) of the output signal.
    ; Play Instrument #1 for two seconds.
    i 1 0 2 10000 220
    e
    /* lfo.sco */

## Credits

Author: John ffitch
University of Bath/Codemist Ltd.
Bath, UK
November 1998

New in Csound version 3.491

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