Intense Tech #08 — DOTCNT's LSDj Wave Cruncher (Defense Mechanism)

author Defense Mechanism
date 2019-06-25
article Intense Tech with Defense Mech, article 08 (the crunch command line and its flags)
created 2026-08-30 · updated 2026-08-30

How to turn a one-note sample into an lsdj wave-synth instrument with lsdj-wave-cruncher, by defense-mechanism (intense-tech) — the companion of the library article s-intense-tech-05-wave-cruncher-instrument-library.

Key claims#

  • The cruncher (by Ada, alias DOTCNT) automates "the downsampling of a single sample into the format that works with the LSDj wave synth", so the result can be played at any pitch, bent and arpeggiated, unlike kit samples. The original needs node and Python; Defense Mechanism compiled stand-alone binaries (GitHub user urbster1).
  • Input: a .wav of one tonal note. Sounds rich in overtones — bells, FM e-pianos, steel drums — work; noisy or non-tonal sounds (snare drums, train whistles, vibraslaps) do not.
  • Syntax: crunch SAMPLE.WAV NOTE|FREQUENCY|auto --flags — the pitch as a note name (A4), in Hz (440) or auto (detection takes 30–60 s and can fail on complex waveforms; the e-piano detected at 136.48 Hz).
  • Flags: --linear takes one cycle from each of 16 equal slices of the whole sample (default: the first 16 cycles); --exp takes more frames from the attack and fewer from the decay; --normalize maximises the level first ("generally results in better-sounding synths"); --channel=0|1 picks the left or right channel of a stereo file; --output=name.snt names the result; --analyze only reports the detected frequency, useful before batch runs.
  • Example run: 311,847 samples at 44.1 kHz, 965 cycles, "taking frame every 60 cycles" for the linear mode.
  • After patching (see article 05), set PLAY ONCE, LENGTH 3, SPEED 3 as a starting point and adjust to the tempo; each crunch may need different instrument parameters. Good results can be contributed to the lsdjsynths library.

Practical takeaways#

Crunch with a known frequency to save time, try --linear and --exp on the same sample, normalise, and expect to tune LENGTH/SPEED per instrument.

Pages touched#

lsdj-wave-cruncher · wavetable-programming · liblsdj · lsdj · intense-tech · defense-mechanism

source file wiki/summaries/s-intense-tech-08-dotcnts-wave-cruncher.md · graph