I’ve been making an electric clavichord over the last few months and have recently finished it, although I’m sure I’ll be tweaking it for a while. Above is a short video documenting the process and demonstrating the instrument.
Traditional clavichords have bent key levers so that the equidistant keys can strike the strings at the correct (non-equidistant) points. This was too much for my limited carpentry skills and also my limited toolbox, so I opted for straight levers, angled so that the “playing” ends of the keys converge on points which are approximately equidistant.
The keys are all made from standard pre-cut wood from a DIY shop (I think it’s 8x8mm). The sharps and the little blocks to hold the tangent nails are all made from the same stuff. It turned out that a lot of the wood wasn’t quite square (which explains why it was half price), so some of the sharps poke up at slightly odd angles.
This skewed keyboard is actually not too hard to play, although it would be difficult to scale up much beyond two octaves.
The clavichord has twelve strings and is double-fretted (the C is triple-fretted), which means it has two tangents for each string – the tangent is the metal part on the key which strikes and frets the string. Traditional fretted clavichords were fretted so that rarely played discordant intervals, like minor seconds, were played on the same string. What’s slightly unusual about my design is that each string is fretted on the octave, meaning that any harmonic interval is possible except the octave.
I had a few reasons for designing the keyboard this way. Firstly, as a pianist I play a lot of octaves and I wanted to encourage myself to use more tone colour in chords. Secondly, each string’s tangents are easily worked out by doubling the string length, which means that the skewed keyboard can be arranged more efficiently without keys which are very close together at the top and very far apart at the bottom, as they would be if fretted to play semitones on the same string. Thirdly, and most importantly, the keyboard is easy to retune to different scales and temperaments, which is much harder on a traditional fretted clavichord. Tuning the D string (for example) tunes both of the D’s.
In the DIY shop across the street from me I found a bag of these strange blade-headed nails, I think they are something to do with carpets. They make perfect tangents. I filed the bladed edges down a bit to prolong the life of the strings.
The twelve strings are all the same gauge. My early experiments indicated that an electric guitar D string sounded pretty good over two octaves when tuned at the length I wanted. I went to my local music shop and found a bargain box of half-price strings, including exactly twelve .28’s (quite a heavy D), so I bought the lot.
A while ago, a friend gave me some cheap mandolin tuners, which come in two rows of four. I managed to find the same type and bought another set, then used a hacksaw to saw one of the rows in half so I could have six each side.
During the process of making the clavichord I was talking to a friend about the pickup I was using (a very old humbucker), and the fact that the strings were very variable in volume. He managed to sort me out with a custom-made extra long humbucker pickup, which just sounds fantastic. If you’re in East Anglia and have a problem with a stringed instrument, I can’t recommend him highly enough! Olley Neale guitar setup and repair.
All in all I’m extremely happy with this instrument. I’m going to play it in for a while and see how long the strings last, then think about performing live.