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lag

Exponential Lag

Plugin opcode in scugens.

Exponential lag with 60dB lag time. Port of Supercollider's Lag. This is essentially a one pole filter except that instead of supplying the coefficient directly, it is calculated from a 60 dB lag time. This is the time required for the filter to converge to within 0.01% of a value. This is useful for smoothing out control signals.

Syntax

aout lag ain, klagtime [, initialvalue]
kout lag kin, klagtime [, initialvalue]

Initialization

initialvalue If given, sets the internal state. It defaults to the first value passed

Performance

ain -- input signal

klagtime -- 60 dB lag time in seconds.

kladown -- 60 dB lag time in seconds for the downgoing signal.

Examples

Here is an example of the lag opcode. It uses the file lag.csd.

Example of the lag opcode.
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<CsoundSynthesizer>
<CsOptions>
</CsOptions>
<CsInstruments>

sr = 44100
ksmps = 128
nchnls = 2
0dbfs = 1.0

instr 1
  ; smooth a krate signal  
  kx = floor(line(0, p3, 10))
  kx2 = lag(kx, 0.1)
  printk2 kx2
endin

instr 2
  ; smooth an audio signal
  kmidi = floor(line(60, p3, 72)/2)*2
  afreq = upsamp(mtof(kmidi))
  afreqsmooth = lag(afreq, 1)
  a1 = oscili(1, afreq)
  a2 = oscili(1, afreqsmooth)
  outch 1, a1
  outch 2, a2 
endin

</CsInstruments>
<CsScore>
i 1 0 5
i 2 0 10

</CsScore>
</CsoundSynthesizer>

See also

Standard Filters: Control signal filters

Credits

By: Eduardo Moguillansky 2017