from this wikipedia page, for those who are unfamiliar with the mbira:
"The mbira (aka likembe, mbila, thumb piano, ...) is a musical instrument consisting of a wooden board to which staggered keys [technically "lamellae", which may be metal or bamboo] have been attached, often fitted to a resonator.   Usually classified as part of the lamellaphone family, it is also part of the idiophones family of musical instruments.   In some places it is also known as a sanza."
though some are configured with an array of keys capable of producing fully chromatic scales, mbira, like harmonicas, are more commonly limited to tones within the range of musical keys sharing a related set of intervals (such as G mixolydian / A minor / C major, etc.).   the proper name for a specific type of mbira seems to refer to both its physical configuration and place of origin.
the "color" of sounds produced by all instruments- that is, the unique quality of sound that distinguishes each from another- is a function of their physical forms.   within a finite range, and varying with the "touch" of the person playing, each creates specifically "shaped" waveforms at certain pitches, subject to Attack-Decay-Sustain-Release (ADSR) envelopes.   the attack is a combination of the time it takes a note to reach peak volume and the manner in which it does so.   decay is the opposite, describing the note's fall in volume from its initial peak to the level at which it rings (sustain).   eventually the sustain gives way and the tone dies out (release).   mbira tend to have an attack that can vary from sharp to blunt, with a relatively loud peak, and a quick decay, followed by a long, smooth sustain/release curve that's almost a hum.
they sound to me like a quiet cross between a xylophone and steel drums, with a little wind chime thrown in, but there's also an element of scraping to the sound- the edge of the 'keys' scraping against the fingers- that's pretty unique.   in Africa, people often attach bottle caps, shells, or similar things to the sound board, which create a buzzing sound, supposed to attract the spirits of the dead- important since the instruments are often played at religious gatherings.   aesthetically, for me, they recall African, Asian, Caribbean, and Central American music, which may say more about the universal commonalities in music than about the instruments per se.
i kept thinking to myself how simple it looks to make one of the more basic ones, apart from achieving the right tones with the tines, which would take some trial and error.   i also think this would be a great gift for a kid, so i looked them up.   they're available from a lot of manufacturers over a wide range of prices.   should either of my readers decide to buy one at some point, consider looking for one on amazon.com, 'cause if you do, and buy one, i'll make a tiny little percentage of the purchase price.   (actually, if you click through any amazon link on this blog, and then buy anything through them during that browsing session, i make a little something.) heck, buy one for me! i kinda like the one on the right...maybe i'll put it on my wish list.
anyway, since they come from Africa, where they've been played for at least a thousand years, it seemed fitting to start there.   the mbira pictured in the video above seems to be a mbira huru.   the piece was probably played on a different instrument, the mbira dzavadzimu ("voice of the ancestors"), which is considered a religious instrument, and is the national instrument of Zimbabwe.   incidentally, i have no idea if that first piece of music is actually African, or particularly indicative of any African style.   i'm certainly no expert on world music or Africa, and i suspect "African music" is an oversimplification anyway.
the mbira in this next picture and video is fully chromatic, as this very nice PDF shows.   the physical configuration makes it one of the most versatile instruments in terms of fingering.   i'm not familiar with this particular composition, but it's a familiar-sounding malagueña or a piece in the malagueñas style.   though many pieces of music bear it as their title, the term refers more generally to a flamenco style of playing, and a type of Central American folk music.   more info here and here.   the mbira migrated from Africa to Central America a long time ago, and was incorporated into the indigenous folk music.   the musician in the video is named Patti.   i borrowed the picture from her myspace page, which has a bunch more videos.   she also has a youtube channel.
in contrast to the last, this next video shows an improvisational jazz piece by Patrick Hadley.   Hadley's mbira (which he also likely made, as he's a craftsman with the manufacturer, Array Instruments), has a 5-octave range, and incorporates a custom piezo cable pickup, allowing amplification, direct recording (as he's done here), and signal processing.   the recording shows definite delineation between stereo channels for different registers on his mbira...possibly two separate pickups.   these retail for about $2400, about the same as a high-end acoustic guitar.
one more from Hadley, which starts with a couple good shots of his instrument.   Array makes a few interesting non-standard instruments, my favorites of which are probably this mbira, their psaltry, and their nail violin.   that last link has pictures of them, and audio clips of them played solo, together and with more conventional instruments. Hadley has a youtube channel too, here.
can't resist throwing in one more link.   mbiras like the one shown after the jump are usually called kalimbas.   i like this guy's technique, using his thumb to baffle the sound hole, finessing it almost like you'd do with a wah pedal on guitar.   he's pretty prolific with the video posts, too.   more power to him!   check him out.