Nuts and Volts - July/August 2018

play, not the one that is currently playing.

Playing the MIDI lyre is done with a plucking type of motion that is a quick touch and release. If you touch a string, it will not sound until you release it. Touch sensor reliability can depend quite strongly on skin resistance, so if you have particularly dry skin, you might find that your touch is not always detected.

To solve this problem, you may need to moisten your fingers slightly before playing. In fact, it’s quite useful to keep a damp sponge or towel next to you while you play. You can play single notes or chords because the instrument is fully polyphonic.

The other way to play the lyre is to strum it by dragging your fingers across several strings. The instrument works very well in this mode. (In a future article, I’ll describe a simple modification that turns the MIDI lyre into an autoharp for playing strummed chords.)

Putting It All Together

Now that you have a working MIDI lyre, you need to package it all up in some way so that it’s easy to transport and play.

There are any number of ways you can do this, and provided you still have access to the strings, buttons, and ports, you can package it as you choose.

I like to make the instrument look like a lyre. The easiest way to achieve this is to mount the instrument on a U-shaped piece of MDF, Perspex, or ply as shown in Figure 7. I find 6 mm is a good thickness for the sheet material because it’s rigid enough without being too heavy. My MIDI lyre is shown in Figure 7.

I call this a “skeleton lyre” because I keep the electronics exposed so I can easily experiment and make changes. For a more robust instrument, you can cover the electronics apart from the buttons and ports.

The shape I have chosen is roughly based on the Saxon lyre from the seventh century C.E. that was found in a burial site at Sutton Hoo, England.

Figure 8 shows the plans for this instrument if you’d like to copy it. NV

■ FIGURE 8. Plans for the MIDI lyre frame that are loosely based on the

Sutton Hoo Saxon version.

July/August 2018 33

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