class SinGen {
    SinOsc @ s;
    Gain @ g;
    
    // constructor work around
    fun SinGen SinGen(float freq, float gain, UGen out) {
        SinGen sg;
        SinOsc so @=> sg.s;
        Gain ga @=> sg.g;
        freq => sg.s.freq;
        gain => sg.g.gain;
        0 => sg.s.op;
        sg.s => sg.g => out;
        return sg;
    }
    
    fun void beep(dur d) {
        1 => s.op;
        d => now;
        0 => s.op;
    }
}


SinGen gens[0];

gens << (SinGen sg).SinGen(400, 0.04, dac)
	<< sg.SinGen(800, 0.02, dac)
	<< sg.SinGen(1600, 0.02, dac)
	<< sg.SinGen(3200, 0.02, dac)
	<< sg.SinGen(6400, 0.02, dac);

fun void mod() {
	SinOsc s => blackhole;
	0.5 => s.freq;
	while(true) {
		(((s.last()+1)/2)+1)*200 => gens[0].s.freq;
		2::ms => now;
	}
}

spork ~ mod();
me.yield();


while(true) {
	for( 0 => int i; i < gens.size(); i++ ) {
		spork ~ gens[i].beep(200::ms);
		me.yield();
		100::ms => now;
	}
}