Ruben's Tube

So, coolest thing ever... they call it a Ruben's Tube and basically what it does is turns fire into an music equalizer.

The device was created by a German scientist called Heinrich Rubens in 1905. He discovered that one could demonstrate a standing sound wave by playing music into a gas filled pipe with uniformly distributed holes drilled on top in a line. His original tube was about 13 feet long and had over 100 holes drilled in the top.

For the past few days my friend and I have been building this pyromaniac/music lover's dream, though on a much smaller scale. Ours was only 3 feet long and had 56 hole, but still just as awesome. The materials we used were:
-3ft. ventilation duct
-2 brackets to fit
-propane (we used 2 small camping propane tanks)
-tubing (1/2in diameter)
-2 hose t-connector
-2 hose splicers (1/2in diameter)
-2 propane control valve (pretty much a simple blow torch adapter)
-latex sheets (we cheated and cut up latex gloves to fit)
-scrap wood
-speaker to fit the the diameter of the ventilation ducting
-old computer speakers you don't mind disassembling
-assortment of screws
-plumber tape
-duct tape
-silicon epoxy
-teflon tape

So to start off we took the ventilation pipe and a tape measure and marked dots for holes starting from the center and working our way out. The dots were about 1/2in apart and we left 4in clear from the edge of the pipe. Next, we took a hammer and a nail and slightly dented each mark to make it easier for for the drill bit to stay in place as we drilled. Next we drilled the holes using a 1/16 inch drill bit.

(this here is my friend being a boss...)

Next we constructed the diaphragm. This was one of the most important parts of the project because this is what controls the gas inside the ventilation duct (side note, make sure to take out the second insulation pipe inside the duct, it will interfere with the sound waves and the gas pressure). We taped the edges of both ends of the duct so the metal would not tear the latex sheeting. Stretching the latex over the ends of the pipe, we made sure there were no wrinkles and we taped it down taught. You want the latex to sound like a drum if you tap it. There does not need to be a diaphragm on each side of the pipe but we did it anyway for future experiments.

Next, we started to install the fuel input system. For this we drilled two 1/2in holes in the duct so the gas would evenly distribute gas inside the tube and installed the hose splicers into the holes. To make the input system gas tight we layered on silicon epoxy around the perimeter of the splicer to fill any gaps we then used our tubing, hose t-connector, and silicon epoxy to make an air tight input system like such:

(in some adjusting we added another propane regulator for another tank, there is only one in this picture)

After putting teflon tape on all the appropriate screw tops we started assembling the speaker system. For this I just combined an old set of computer speakers I took apart and a 3in diameter speaker to fit the diameter of the duct. I took the circuit board amplifier from the speakers, connected them to the speaker, and mounted them on to some plywood scraps I found and cleaned off. This was completed using just a few screws and some plumber tape.

Lastly, we connected and mounted all of the items onto a long piece of plywood I found, and basked in the glory of completing a work of art.

                                                    (Wyatt and I)

(Clayton and I)                              (Wyatt and Clayton)

(video will be uploaded shortly...)
OHH.. also be very careful... things can blow up, and will. It happened to us a few times in the process of making this.