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Pluck

SourcespluckLight CPU

Karplus-Strong plucked string / drum — trigger + decay + damp.

What it does

Karplus-Strong plucked-string / drum voice.

Wraps daisysp::Pluck (Csound algorithm). Init takes a file-scope 256-sample impulse buffer; Process(float &trig) re-plucks whenever trig != 0, so a file-scope prev_trig snapshot feeds it a one-sample rising edge via a materialised lvalue. Mode is baked at init.

Parameters

  • Decay

    decay
    Default 0.7Range 0 … 1

    How long the note rings before dying away. ⚠ It also sets the lowest pitch the tile can reach, because the algorithm works from a fixed 256-sample buffer and the decay length is bound up with it — asking for a very low note and a very long decay at once is the case where this tile disappoints. Per-sample, so it can be modulated between plucks.

  • Damp

    damp
    Default 0.7Range 0 … 1

    How much the tone is filtered on each pass around the delay line, which controls how quickly the bright part of the pluck dulls into a soft tail. Low values keep the string bright the whole way through and sound synthetic and buzzy; higher values behave more like a real string, where the attack is bright and the tail mellows. Distinct from Decay, which is how long it lasts rather than how it changes.

  • Amplitude

    amplitude
    Default 1Range 0 … 1

    Output level of the tile, 0 to 1. Because Pluck has a native amplitude control this scales the string itself rather than being a separate VCA stage after it, so it is the right place to set a fixed level. For playing notes with an envelope, wire the envelope in rather than trying to automate this.

  • Decay Mode

    mode
    Default recursive

    Which of the two Karplus-Strong averaging schemes the delay line uses. Recursive is the brighter and more metallic of the two, keeping more high end alive as the note decays. Weighted Average rolls the top off faster, giving a softer, rounder, more nylon-like string. ⚠ Baked at build time, so this is a choice about what the patch is rather than something to sweep.

Wire a pad/gate to Trig — each rising edge re-plucks. Decay sets how long the note rings (also the lowest pitch the 256-sample buffer reaches), Damp the filter dampening, Amplitude the level. Freq / Decay / Damp accept Mod sources; Mode is baked. Recursive = brighter, Weighted Average = softer.

Ports

In

  • Trig trigger
  • Freq frequency
  • Decay decay
  • Damp damp

Out

  • Audio Out output

Audio Control

Inputs

Trig
Rising edge re-plucks the string.
Freq
Pitch in Hz.
Decay
Ring time, 0 → 1.
Damp
Filter dampening, 0 → 1.

Outputs

Audio Out
Plucked-string output.

Rules and gotchas

  • Decay Mode is baked at build time.