Awesomeness.
With a little help from my (thermionics) senior electronics instructor, I built a Theremin when I was a senior in high school.
We cut the middles out of two steel pie plates for the "air" capacitance sensors. Otherwise it was all tube/valve operated. Most of the parts came from a dilapidated television that we scavenged.
That's awesome.
I was a kid at eighteen and one of the coolest things I had ever seen at that age was a theremin.
I also had an awesome electronics instructor. I actually learned more advanced math, geometry, probability and calculus stuff from that one man in that one year than the previous three years of such studies. He basically said that this stuff is "basic" if you want to know how to build electronic circuits that are predictable in function.
That same year as a "Christmas project" I built a sound to light controller (this was before I built the theremin) which divided the audio spectrum into eighteen channels. I chose eighteen because I had already prepared to do something and needed eighteen distinct controls. I built a box out of plywood that was about two feet deep and six feet tall and wide (that was the largest "diamond diffuser" clear material I could find) and strung lengths of Christmas lights inside in eighteen different patterns, some around the outside, some crossing and some star, oval, square etc. shaped and two that were random.
As I played music the controller would take the music, dividing it into the eighteen channels and play certain light patterns inside the box in sequence to follow the intensity of the music. I had a control box where I could add "preference" or "priority" to any one of the eighteen channels, combine or separate them.
So every light (there were about three thousand small lights wound inside the box) passing through the diffuser would appear as a diamond/star when actuated and strings of them simultaneously made quite an impression. It was quite a light show once I had it adjusted so that the music was balanced with the lights.
That was my mid term project and it was all done with solid state electronics, no tubes.
I got an "A."
ponds from now on.