A comparator is about useless for that, you need an integrator. Even then though with echo it won't work quiet right. You'd need to use three mics and triangulate the volume source. Four if you want to sense it in 3D. Three sensors will only sense accuratly on the plane the sensors are in. It's a lot more complex than you might think.
Hi, Triode, No, I just want it to look alive to sound.
Many years ago a guy rigged up a head on a snake like body which moved towards the sound source. The body was a flexible tube with three steel cables running up the middle.
It was installed in a museum.
The cables moved the head forward , left or right.
I had a video of the beast which showed it lunging towards the people
I have lost the video and circuitry.
I just want my project to follow the sound source.