World Music ConcertMbira Concert
The mbira of Zimbabwe consists of 22 to 28 metal keys mounted on a gwariva (hardwood soundboard) made from the mubvamaropa tree (Pterocarpus angolensis). Although the metal keys were originally smelted directly from rock containing iron ore, now they may be made from sofa springs, bicycle spokes, car seat springs, and other recycled steel materials. The mbira is usually placed inside a large calabash resonator (deze) to amplify it. A mutsigo (stick) is used to wedge the mbira securely inside the deze. The mbira is played with the two thumbs stroking down and the right forefinger stroking up.
Either metal beads strung on a wire, or bottle tops or shells mounted on a metal plate, are placed on the lower portion of the mbira soundboard to add a buzz which varies from a soft hiss to a tambourine-like sound. Bottle tops or shells are also mounted on the deze to increase the buzz. The buzz is considered an essential part of the mbira sound, required to clear the mind of thoughts and worries so that the mbira music can fill the consciousness of the performers and listeners. The buzz adds depth and context to the clear tones of the mbira keys, and may be heard as whispering voices, singing, tapping, knocking, wind or rain.
Many different mbira tunings are used, according to personal preference. The only requirement is that two instruments played together should generally agree in tuning. If the same sequence of keys is played, the music is considered to be the same mbira piece, even if played on instruments tuned with completely different intervals. For example, the gandanga (outlaw) tuning, also known as mavembe (people with speech defects) tuning, has a different interval relationship between keys than the more common nyamaropa tuning. The pitch of an mbira is also a matter of personal preference, ranging from high to very deep. Each instrument has a range of three octaves, or slightly more.