The vina bambina is a monochord designed to be played on both ends of the string, leading to structurally determined harmonies and dissonances that all center on the fundamental. I currently have an electric bambina, with a pickup at both ends of the string, and an acoustic bambina, shown here.
Solo Bambina recordings: https://soundcloud.com/dsconrad
Graph of note relationships on the vina bambina: HERE
The wildwave consists of two sine wave signals processed through a mechanical/electric resonator. It is played by controlling two audio oscillators with their signals mixed equally, amplified, and sent to a transducer, which consists of a drive post (plastic foam or cork) attached to the drive coil of a speaker. This speaker-head is suspended over a balanced metal plate so the post delivers vibration to the plate, but the linkage is not fixed, so it is free to bounce on the plate or drive it. The resulting vibration of the plate is picked up with a piezo contact mic and sent to an amplifier and speaker.
The math department at Poly threw away a globe-shaped chalkboard that had apparently been used to teach spherical geometry many years ago. With the paint scraped off I found it was an iron shell. After many false starts I decided to cut it with a nibbling tool and found that in the area of a cut the metal would ring, so I tried many different patterns to make different pitches and tones. By the time it was finished I realized that consistent use of simple X shapes would have made a much better sound, but I don't ever expect to find another sphere of sheet iron with which to refine the design. Even so I enjoy its odd sound.
Guitoura - an acoustic guitar strung with four strings and a flat bridge so it acts like a tamboura.
This flute is a tube about 18" long with a squeeze bulb at the bottom filled with water. Played like a pan pipe while sqeezing the bulb. Impossible to control - very glissy. Invented when I was about 14 years old.