// patch
adc => Gain g => OnePole p => blackhole;
// square the input
adc => g;
// multiply
3 => g.op;

// set pole position
0.99 => p.pole;

// loop on
while( true )
{
    if( p.last() > .8 )
        <<< "BANG!!", p.last() >>>;
    0.01::second => now;
}