I made this in the summer of 1997. The bars are 1-inch galvanized plumbing pipe. The bottom of the pipes are hung with heavy-gauge speaker wire seperated by eye-screws and rubber washers. The top of the pipes rest on insulation foam. The wire on top keeps them from bouncing out of place. The frame is mostly wooden hand-railing. This thing is heavy, almost 50-pounds.
There are 28 pipes with 18 notes in the lower octave and 9 in the higher, plus one additional octave note. It's mostly in the key of B, by chance. It plays best with harder mallets gamelan-style. You can also roll or bounce different spheres and cylinders across it.
The Galvanophone appeared in the December 1998 issue of Experimental Musical Instruments.
Build your own! Instructions below.
|Step One: Prep the pipes
Cut 28 1" diameter galvanized pipes in lengths of 36", 35", 34", etc. down to 9" with a hack saw
Drill a hole through each pipe at exactly 22.5-percent from one end (ex. 10" pipe has a hole at 2.25" from the end)
Clearest tones come from the 9" to 21" length pipes
|Step Two A: Build the frame
Screw together a wood frame
Angle of top bar must line up at exactly 22.5-percent from the end of each pipe
Use rubber bumpers on bottom to protect surfaces
|Step Two B: Build the frame
Wood stairway railings supply the main support bars
1" x 2" wood for the ends
1" x 3" wood for the cross supports in the middle
The top bar is raised up to keep the pipes level
|Step Three: Mount the pipes (bottom bar)
Pre-drill and insert screw-eyes about 1.62" apart
Speaker wire goes through the holes in the pipe
Rubber insulation (or thin rubber washers) insulates the pipes from the screw-eyes
Speaker wire is pulled tight and anchored with smaller screw-eyes
|Step Three: Mount the pipes (top bar)
Pre drill for "roofer nails" (with a lip so the speaker wire doesn’t slide down)
Nails are sheathed with shrink tubing to insulate pipes
Apply adhesive-backed insulation foam to top bar for pipes to rest on
Nail in nails
Wind speaker wire (keeps pipes secure for transport and storage)
Helpful Hint: Use a triangle or a t-square off of the bottom bar to get the proper spacing for the nails on the top bar. For example a 1.62" width between the screw-eyes on the bottom bar will become a 1.65" or so distance on the angled top bar. Before you put the frame together or drill any holes it helps to lay out all your pieces in position to make sure it all looks right. All these instructions are pretty loose except the 22.5-percent distances. If these are off by too much the pipes will not resonate well.