June 23, 2006
A Resonant Body

OK, you don't have to be a physicist to have fun with the physics of the kalimba. Check it out! The most common types of Hugh Tracey Kalimba are the Alto and Treble, each with their own resonant boxes. (AMI has just made a few dozen Pentatonic kalimbas mounted on ALTO boxes. My friends are having LOTS of fun with these, but the world at large hasn't caught on to them yet.) The boxes will be the subject of many Tips to come, but for today, just know that these boxes make the kalimbas louder. The tine you pluck vibrates, and that vibrational energy gets the wooden box to vibrate, and the box vibrating gets the air inside the box to vibrate.

Most traditional kalimbas had metal tines mounted on a flat wood board, without a resonant box. The Hugh Tracey Celeste Treble, Celeste Pentatonic, TM Alto, and Karimbas are all mounted on a flat board. If you hold one in your hands while you pluck a tine, you can totally feel the vibrations in the board. That is energy waiting to be harnessed. You can transfer that vibrational energy to another body. Now, our bodies are soft and don't vibrate so well; rather, our hands tend to dampen the vibrations. But take your board kalimba and place it against a table top or a window pane and pluck it. It should be MUCH LOUDER. You have transferred the vibrations to that table or window, which is now a larger vibrating surface, radiating the sound through the air.

In Zimbabwe, the mbira (the most advanced traditional African kalimba) is often played inside a large calabash gourd. The mbira is firmly wedged in so it makes good contact with the gourd. The mbira board vibrations are transfered to the gourd, and the gourd makes the air inside it vibrate. The air inside the gourd will resonate (vibrate sympathetically) to a whole range of notes, but some may be louder than others.

In this odd world that I live in, natural materials such as large calabash gourds are hard to find, but large plastic bowls from the second hand store are easily found. I found one for $1 which boosts the karimba's volume by a huge amount and makes a beautiful clear tone, and you can see it in the photo below. Click here to watch a video.

NOTE that at the beginning of the video, the karimba is not touching the bowl and is not very loud. When the karimba goes inside the bowl and touches is, it suddenly becomes much louder, but some of the notes don't sustain as long. Why?

I dare you to take your kalimba into a second hand store or to a garage sale and try out all the large bowls until you find one that works just right! Well, I did it, and nobody locked ME up!