cool idea to have odd sounds amplified by a box into a transducer into an amp then add reverb to it in the mix or whatever effects you want. That spring in the lower middle is really cool. It wobbles a long time and has a raspy sound to it.
I´d say a little black ink, goats blood and some fake splatter effects and the box would look like it sounds... alternatively you could always just heat the springs up to glowing-red and put some barbwire and razor blades in strategic positions in and around the box and it will not only look the part after a while but there will also be these subtle screams and heavy breathing from the player in pain that can be utilized... nice demo this is a good formfactor and some usable and impressive sounds.
What do you use to connect stuff to the box? Any particular sizes you can recommend? I've got the piezo and everything wired up but can't figure out how to start connecting my springs and other stuff besides grounding bars for some of it