The SynthDefs for my Christmas EP

As threatened, I have once again made some Christmas music.

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The notes in the 5 movements all come from the same pop song, but in 4 of the movements, they pass through a class I (accidentally) wrote called MidiMangler. It’s undocumented, but the constructor expects the kind of midi events that come from SimpleMIDIFile in wslib and the .p method spits out a pbind.

The instruments are some of the sample I used a couple of years ago, but the organ is new. It’s based on one from but modified to be played with a PmonoArtic.

SynthDef(\organ, {| freq = 440, gate=1, amp=0.25, pan=0 |
    // from
    var lagdur, env, saw, panner;

    lagdur = 0.4;

    saw =,, 0.8) *, Rand(0.0, 1.0)).range(0.7,0.8));

    env =, 0.7), 1, Rand(1.0, 2.0), Rand(-10.0, -5.0)), gate, doneAction:2);

    amp = / 4) * (, 0.1), lagdur) + 1)); // tremolo

    panner =,,1), env * amp);, panner);

The other instruments are the default synthdef *cough*, a Risset bell and Karplus Strong – taken directly from a help file with no changes. These are presented at the bottom for the sake of completion. The other sound is a bomb sample I found on freesound.

The video is taken from an atom bomb test video, but slowed down and stretched. I used ffmpeg to do this. The original film was 24 frames per second. I used a ffmpeg filter to create a lot of extra in-between frames and then, separately, changed the frame rate to be much slower. The original film was a bit over 20 seconds and got stretched out to 15 minutes. The really low frame rate is a bit choppy, but I think more tweening would have just increased distortion. The commands for that were:

% ffmpeg -i trees-bomb.mp4 -filter:v "minterpolate='fps=180'" 180trees.mkv
% ffmpeg -i 180trees.mkv -filter:v "setpts=33.4*PTS"

The other day, I read someone putting for the idea that apocalyptic thinking is so profoundly unhelpful as to be self-indulgent. Climate change is not going out with a bang, but a very prolonged whimper, whilst, for the duration, failing to make any significant changes. We can address it and avoid many of the worst impacts, but we need to get very serious about it immediately. If we can build thousands of expensive, terrifying bombs just in case there might be a war nobody wants, surely, we can afford to spend some of that resource averting a disaster that we know is actually coming.

SynthDef(\bell, // a church bell (by Risset, described in Dodge 1997)
    {arg freq=440, amp=0.1, dur=4.0, out=0, pan;
        var env, partials, addPartial, son, sust, delay;

        freq = freq * 2;
        sust = 4;
        amp = amp/11;
        partials =;
        delay = Rand(0, 0.001);

        //bell = SinOsc(freq);

        addPartial = { |amplitude, rel_duration, rel_freq, detune, pan=0|
          *rel_freq+detune, Rand(0, 2pi), amp * amplitude* (1 + Rand(-0.01, 0.01))), pan)
                    Env.perc(0.01, sust*rel_duration* (1 + Rand(-0.01, 0.01)), 1, -4).delay(delay), doneAction: 0))
            ).tanh /2

        //addPartial.(1, 1, 0.24, 0, Rand(-0.7, 0.7));
        addPartial.(1, 1, 0.95, 0, Rand(-0.7, 0.7));
        addPartial.(0.67, 0.9, 0.64, 1, Rand(-0.7, 0.7));
        addPartial.(1, 0.65, 1.23, 1, Rand(-0.7, 0.7));
        addPartial.(1.8, 0.55, 2, 0, 0); // root
        addPartial.(2.67, 0.325, 2.91, 1, Rand(-0.7, 0.7));
        addPartial.(1.67, 0.35, 3.96, 1, Rand(-0.7, 0.7));
        addPartial.(1.46, 0.25, 5.12, 1, Rand(-0.7, 0.7));
        addPartial.(1.33, 0.2, 6.37, 1, Rand(-0.7, 0.7));

        son = Mix(partials).tanh;
        son =, 0.06, Rand(0, 0.02));, sust * 1.01), doneAction:2);, son);
SynthDef("plucking", {arg amp = 0.1, freq = 440, decay = 5, coef = 0.1, pan=0;

    var env, snd, panner, verb;

    freq = freq + Rand(-10.0, 10.0);
    env =, decay, 0).delay(Rand(0, 0.001)), doneAction: 2);
    snd =

        maxdelaytime: 0.1,
        delaytime: freq.reciprocal,
        decaytime: decay,
        coef: coef);

    //verb =;
    panner =, pan);, panner);

Published by

Charles Céleste Hutchins

Supercolliding since 2003

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