0.15 => dac.gain;

SqrOsc a;
SqrOsc b;
SqrOsc c;
SqrOsc d;
[a, b, c, d] @=> SqrOsc oscs[];

LPF lpf => ADSR e => dac;
7000 => lpf.freq;
e.set(10::ms, 500::ms, 0.5, 50::ms);

// chord root in MIDI note number; 60 is Middle C
55 => int root;
// array of intervals relative to the root
[0,4,7,11] @=> int chord[];

for (0 => int i; i < 4; i++) {
    root + chord[i] => Std.mtof => oscs[i].freq;
    oscs[i] => lpf;
}

e.keyOn();
1::second => now;
e.keyOff();
2::second => now;