Post 15: Still more musings about what the next "Music Making Machines" might be.

      I have long been in love with the hurdy-gurdy.  I was born in a region of France called Morvan, which has traditional folk dance music where the hurdy-gurdy generally is the only instrument. When we had an outdoor wedding party there back in 1975, my father asked one of the few old-timer musicians to come and play for us. It was great, we even got to play his beautiful old vielle.  I considered building one back then, but never did. I wanted to buy an old one, but they were rare and expensive. I went on to other things.

     There has been a considerable revival of the hurdy-gurdy in recent years, especially in Irish music, and a number of luthiers are making them again, improving on the age-old design, even making electric ones.       I recently discovered a European virtuoso that plays incredibly beautiful, haunting, interesting and soulful music on an electrified instrument: Guilhem Desq

     It's a very old instrument found more or less all over Europe, derived from the Organistrum, which goes back a thousand years.  It was mostly used in churches back in these times, and was much bigger than the later 15th-century Hurdy-Gurdy. It required two people to play, as depicted in this sculpture from a 12th-century Spanish church:

     Because of its large size and its longer strings, it's sound inside a church must have been similar to a small organ, the instrument that would come to eventually replace it. 

     I have been dreaming of making a really big electrified one, that could really fill a space with the same deep resonant tones as the organ. The biggest and longest string commonly available string is a double-bass E string, which is tuned at 41 hertz. I ordered a set and received it yesterday. 

    I wanted to test it immediately, so I just used a stick of Guatemalan caoba I had, fitted it with a very basic tail, two guitar tuners, a small guitar pickup, a 1/4" rod as a nut, and a piece of 1" tubing as a bridge. I want to get the deepest sound possible, so I took full advantage of the 62" length of the string, and have the bridge to nut distance maximized at 51", instead of the standard 43" scale of a 4/4 double-bass. That is 20% longer, and I am hoping to get at least a low D, maybe even a low C. To make the tone richer, I added the D string, and plan to tune it an octave higher than the lowest tone I get from the E string.

     I also improved my slightly out of round test wheels, and cut two new 8" disks out of high-density fiberboard, one 1/4" thick, the other 1/2". I fitted them with the flanges extended by an aluminum disk to avoid wobble, and rubbed the edges with dark rosin:

     I tuned the big E string to a low C and the smaller D string to an A. It could also be tuned to a C to play in unison. Here is the test video:

    Well, testing has now shown me that the strings sound best when the wheel is rubbing them down or up rather than sideways. With the strings side by side, I cannot do that, or it would require two wheels, which is an option.

      If I want to use a single wheel,  I will have to build a "sideways bridge" with two levels. This is actually not unique, there are other instruments with such a bridge, like the African Kora, which is plucked like a harp:

      But that will change the design of my future "Double-Bass Gurdy". The axle of the wheel will have to be above the sounding board instead of below, and the strings arranged vertically. Using my old MacPro box as a body, it would go something like this: