Ten fret soprano - Ukabosy

John Colter

It ain't what you've got, it's what you do with it
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In another thread, I mentioned an odd ten fret soprano that I made. I may have posted a pic of it in this forum already, but a search did not bring it up.

It is inspired by the Kabosy, a folk instrument from Madagascar. People make their own, out of whatever materials they can find. A Kabosy usually has a narrow rectangular box body, and often (but not always) four metal strings made from single strands unwound from old bicycle brake cables. The tuning is very variable, as is the placement of the frets. Some look extremely puzzling to European eyes.

Mine looks similar to a Kabosy, but the scale and the strings are standard soprano ukulele. I aimed to make it look "charmingly rustic", but apart from some obviously contrived crudeness of construction, my aim failed! It is too shiny and smooth. I used some mahogany which Ken Timms had rejected as too rough for his purposes.Kabosy-uke-Lemur face.jpgUkabosy.jpg

It sounds quite pleasant, but is rather quiet owing to needing a very low bridge. This is because I did not make allowance for the lack of a fretboard when setting the neck angle.

As a tip of the hat to the Kabosy's odd fret placment, I simply left off the two top frets. If I made another, I would join the neck at the tenth fret. That would give it very unusual proportions. There is an image of the face of a Lemur burned onto the back.

Another odd feature was to work out the fret spacings according to "the rule of eighteen".

John Colter
 
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Over on the cigar box guitar site it was pointed out that the modern way of spacing frets according to 17.something, or more accurately using the log contrived distance and then adding a small amount to compensate for string bend when fingering the frets gets you suspiciously close to the rule of 18 with no compensation. Coincidence? I think not.

Love the build by the way.
Would I be wrong in assuming some of those odd looking fret placements on the originals might be a product of slack key tunings like on some mountain dulcimers where you only need every second fret and the odd fifth or so
 
Hi Titch,

The rule of 18, without need for compensation, gives results which are so close to 17.817, with compensation, that it doesn't matter which method you use. They both give accurate fret placement. The luthiers of old knew what they were doing.

I think the Kabosy is derived from very early Arabic influences, so the scales and musical spaces may be completely different from those used in Western music.
 
There has been some interest in this odd instrument on the new 'Headstocks' thread. The headstock had insufficient downward angle and the uke uses a zero fret. To provide the required downward pull of the strings over the zero fret the 'nut' is upside down. The nut usually props the strings up. On this instrument it holds the strings down. Ukabosy Headstock.jpg
 
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Thanks for bumping this! Very cool instrument
 
10 frets, how very metric system of you.
 
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