MIDI files are a smart, effective way to share music for African marimba bands when you can’t share it in person. Here are some tips for producing them, aimed at those with some knowledge already of working with MIDI.Instrument choice. The General MIDI marimba sound typically doesn’t work well, especially in the lower octaves. Instead use the kalimba, #109 (in a range of 1-128). The tone is different, but the dynamics are much closer to what you want.
Sorry, there’s nothing approaching a hosho sound in General MIDI. To mark the beat in complex pieces as a learning aid, you might use the woodblock, #116.
Instrument transposing. If you’re creating your MIDI file with a music notation program, you can keep the written notes in a middle range by transposing just the playback. Here are the settings. (An octave equals 12 semitones.)
Sopranos—up 1 octave
Tenors—no change
Baritone—down 1 octave
Bass—down 1 octaveWith these settings, the treble clef would be used for high soprano, high tenor, and baritone. The bass clef would be used for low soprano, low tenor, and bass.
Note length. The duration of a sound on a marimba is short, so don’t represent it with long notes. For instance, in place of a half note, you would use a quarter note and a quarter rest. A bass note might stretch out to a half note, but nothing longer. If don’t watch out for this, you might easily compose something in MIDI that won’t sound nearly as good in performance.
Instrument placement. With only one instrument sound to work with, keeping the parts distinct is a challenge. Start by “panning” the various instruments to one side or the other for stereo sound. Here are my suggested settings.
Lead soprano—center
First or high soprano—100% left
Second or low soprano—100% right
First or high tenor—33% left
Second or low tenor—33% right
Baritone—66% left
Bass—66% rightInstrument volume. The kalimba sound gets quieter in the lower octaves, and any MIDI instrument gets quieter as it moves away from dead center—so you need to adjust the volumes. Here are some settings to start with.
Lead soprano—90%
First or high soprano—70%
Second or low soprano—80%
First or high tenor—80%
Second or low tenor—90%
Baritone—90%
Bass—100%Phase effects. If two instruments play the exact same note with the exact same tone at the exact same time, that note will sound as if it came from halfway between the two instruments. Since the ranges of the African marimbas overlap, this means you can’t always tell which instrument is playing which note. Here are some ways to avoid such problems.
• Enter the notes manually from a keyboard, so the timing isn’t exact.
• Set a “human playback” option in your program for the same effect.
• In a sequencer, “delay,” “nudge,” or “shift” the playback of entire tracks, moving them slightly forward or backward in time so they don’t exactly line up. In many cases, you can move tracks as much as 5% of a quarter note in either direction without making things sound too far off. You can try the following shifts as a starting point.
Lead soprano—None
First or high soprano—5% sooner
Second or low soprano—5% later
First or high tenor—5% sooner
Second or low tenor—5% later
Baritone—5% sooner
Bass—5% laterIf it’s your composition, you might be able to head off such problems entirely by making sure two instruments never play the same note together, or even play in exactly the same range. This is worthwhile anyway, because phase effects happen in performance too—which is one reason the sounds of a marimba band tend to jumble together. But with so many marimbas with their identical or overlapping ranges, it’s not easy to keep the instruments from stepping on each other’s toes!
Reverb. You can keep your sound more crisp by avoiding reverb. To prevent a MIDI player from adding it on playback, you can set the reverb on each track to 1% or less.
Templates. Yes, it’s a hassle to manipulate all these factors in your source file. The good news is, when you’ve done it once, you can use the file as a template. For a new piece, just replace the notes, make any necessary adjustments such as time signature and tempo, and you’re done.
For a sample of a MIDI file using many of these tips, you can download my arrangement of “Kiss the Girl” from the Mukana Marimba Web site at www.mukanamarimba.com.
May 6, 2007