float grid[16];
for(0=>int i; i<grid.cap();i++){
    std.rand2f(0,1) => grid[i];
}
1 => grid[0];
0 => grid[4] => grid[12];

while (true)
{
    for(0=>int i; i<grid.cap(); i++){
	400::ms => now;
	grid[i] => float level;
	if(level - std.rand2f(0,1) > .3){
	    Instruments.analog_bd(level);
	}
    }
}