[UPDATE: Here’s the final documentation of the installation including videos and sound recordings.]
Dear Interwebz! Since it will take a while until I can post a new project here on my website, I figured it might be nice to let you know what I’m working on right now. My plan is to build a very big hand cranked music box. It will use real instruments – an electric guitar, a keyboard and a drum set. I have worked on the keyboard and guitar mechanisms so far. Here’s a recent photo:
In early summer, the machine will be ready and on public display in a glass pavillion in Wroclaw, Poland. Everyone will be free to operate it 24 hours a day. I’ve drawn a floorplan of the setup as I imagined it, but of course the details might still change. The installation will be called “Music Construction Machine”.
Usually one music box repeats the same melody over and over again. But I’ve decided to build the Music Construction Machine in such way that it generates ever changing melodies. It does that by following an algorithm, which is implemented in mechanical hardware, consisting mainly of ropes, pulleys, springs and weights. The pulleys will drive many different mechanisms, which then will operate the instruments. Besides producing a (hopefully) interesting music, there will be plenty of moving parts to be seen and to be investigated inside the pavillion once visitors start operating the crank.
Below you can see the melody mechanism for the keyboard machine. It uses two pulleys of different sizes, which are driven by one rope loop. Both pulleys produce a linear sinewave movement. Due to their different circumferences, the two resulting sinewaves have deviating frequencies. The linear sinewave oscillations then drive the subsequent mechanisms, which move two carriages left and right over the keyboard. From time to time (triggered by a separate rhythm mechanism), the carriages are pulled away from the driving mechanism and pushed onto the keyboard, where they play two tones at the same time.
Although the mechanisms follow a simple inherent logic, which determines the sequence of tones that will be played, the overall behavior of the system is so complex that the sequence appears to be unpredictable for a listener. The result is a melody which is sometimes harmonic, sometimes not, but it definitely has a lot of variation.
Let’s have also a look at the guitar machine! At the current state this has two mechanisms. One picks the strings and the other operates the fret board. Let’s start with the picks: Six levers are constantly moving up and down, with plectra attached to their ends. All of those levers are moved by individual pulleys – and again – those pulleys all have different circumferences. The result is that each plectrum moves in a slightly different speed up and down and the played melody is basically an interference pattern.
The mechanism below is a ratchet mechanism. It starts with a pulley, which moves a lever up and down. Each time the lever moves upwards, it grabs one tooth of the sawblade-shaped wheel and spins it by 45°. This wheel drives then another lever, which moves a steel pipe up and down the fret board in a sinewave pattern.
You can see the result below. The mechanism creates very psychedelic sounds and the effect is overall very dominant. Which I like. What I don’t like, is the fact that this effect occurs in such a periodic pattern. Therefore, I have decided to add another mechanism to this construction, which will make the pattern appear more irregular.
Overall, I have to say that the work is on a very good track. Initially, I had some issues which were mainly caused by too much friction, but now (almost 200 ball bearings later) I’m very pleased with the behavior of the machine. Everything makes a sturdy impression, which is essential regarding that it will be operated by the public, day and night, without supervision.
The finished installation will be exhibited from June 17th onwards in Wroclaw, which is one of the current European culture capitals in 2016. The Goethe Institut is organizing the exhibition of the machine as part of their Pop Up Pavillon project. I also want to thank Musikhaus Thomann for supporting my construction with a generous donation of instruments, as well as light and sound equipment.