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Exploring The Exotic Instruments In GM/XG/GS Sound Sets

The GM, XG, and GS sound specs are frequently derided for imposing boring uniformity on the synth universe — but in fact they contain many unusual sounds. Dave Stewart, a man who knows a gopi‑yantra from a gankogwe, sheds light on some of the lesser‑known instruments in the General MIDI set, and provides some useful playing tips.

General MIDI is, on the whole, a well‑intended attempt to impose order on the organisation of programs and drum mapping within MIDI sound modules and workstations — although there are those who will always view such attempts at standardisation as the enemy of imagination. Nevertheless, the idea has some obvious advantages; having taken pains to organise a demo involving 12 separate instrumental parts, the user can transfer the sequence to another manufacturer's GM unit and still enjoy the original orchestration, albeit with a slightly different set of sounds. This compatibility offers some comfort to those whose lives revolve around the playback of MIDI files, as well as potentially streamlining the exchange of musical information between collaborators.

The Family That Plays Together

For the purposes of cramming the world's millions of musical instruments into a unit the size of a lunch box, the General MIDI programmers sketched out 16 instrument families (these are shown in Table 1 opposite). Each family was allocated eight different programs, giving a total of 128 sounds. So far, so good — but in an attempt to give everything a descriptive name, the programmers (unwittingly or otherwise) came up with some real howlers: Goblins (#102) for example, is nonsensical, Tango Accordian (#24) is a blatant example of soft drink product placement, and Tinkle Bell (#113) sounds like a euphemism for a bodily function (or worse). Bringing the whole shooting match to an abrupt close is a program called Gunshot (#128), which seems gratuitously violent to me.

It's A Hit — Tuned Percussion (#9‑16)

Joking apart, there are some instrument names lurking within the General MIDI spec which may be unfamiliar to users, and this article is an attempt to explain exactly what those instruments are. Let's start with the family loosely known as 'tuned percussion'. The Celesta (#9) is the small keyboard instrument immortalised in Tchaikovsky's 'Dance of the Sugar Plum Fairy'. Played like a piano, its hammers strike interior steel chime bars suspended over wooden resonator boxes, producing a beautiful, delicate sound which reminds me of a Stage 73 model Fender Rhodes. Having heard a (presumably sampled) celesta featured in a Top 20 dance hit recently, my prediction is that this is going to become quite a hip sound. The Glockenspiel (#10, or 'orchestral bells' in the USA) is laid out like a xylophone, but with shiny bars of steel. Played with hard beaters, the glock's high‑pitched chimes will cut through the densest orchestral arrangement.

The Marimba (#13) and Xylophone (#14) probably need no introduction, but if in doubt as to which of these wooden‑keyed instruments to use, remember that the xylophone is higher‑pitched and has a dryer timbre, whereas the marimba's larger size and tube resonators create a fuller, plummier sound. Samplers and workstations tend not to do justice to the latter instrument, usually rendering its subtle tones harsh and brash. An interesting alternative to the marimba is the Balafon — though altogether more rattly and buzzy, this large African xylophone has a simple, earthy sound which is excellent for melodic rhythm parts and bass lines.

Lumped in with the GM tuned percussion family is the Dulcimer (#16). This is actually a type of zither (a shallow box with strings running between raised bridges) which is played with hammers or beaters. Some companies offer the regional variation of the Santur in this slot — this is a classical instrument from Iran and Iraq, whose quadruple metal strings are played with light hammers (made of wood, cane or wire) with curved ends. [The instrument pictured above is actually a further regional variation of the same idea, this time from China, where it is known as the Yang Chin — Ed.] Notes can be artificially sustained by bouncing the hammers repeatedly in a tremolando style. As a further variant on #16, at least one company offers the Eastern European Cimbalon, a popular folk instrument played with yarn‑covered beaters (if you're wondering how there can be variants like the Cimbalon within a so‑called standard like GM, see the 'Corporate Cooperation' box opposite). The Cimbalon's plaintive melancholy tones famously infiltrated the soundtrack of the film The Third Man. This is possibly the only movie theme which can be played successfully on a steel comb — be warned, I speak from experience!

Hammered dulcimers should not be confused with the North American Appalachian Dulcimer (aka 'Mountain Dulcimer'), a plucked instrument with three steel strings and a raised fretboard down the middle, and a sound akin to a small acoustic guitar or banjo. In my sound library, all these instruments are classified as 'miscellaneous stringed' and grouped together with harps, mandolins and the like — but the GM bods obviously didn't see it that way...

Something In The Air — Wind Instruments (#65‑80)

GM sensibly divides the wind family into reeds (saxes, clarinet, bassoon & oboe) and 'pipes' (flute, recorder, and so on). All instruments in the former group should be well known, but it's worth remembering that English Horn (#70) is also called the cor anglais. A couple of the non‑reed wind instruments may be less familiar; Shakuhachi (#78) is a breathy‑sounding Japanese flute whose traditional playing style relies heavily on the use of grace notes (see the box on page 192). Whistle (#79) sounds straightforward, but does the name refer to a) a tin whistle (flageolet), b) the item of referee's kit, blown to indicate that Dennis Wisell has just made a tackle or c) the breath‑powered, quasi‑musical activity enjoyed by tradesmen of a cheerful disposition? A quick blast on my Korg Trinity's GM 'Whistle' program suggests the answer is c); good news for anyone attempting a cover of the 'X‑Files' theme.

Whether you're familiar with it or not, I can't resist this opportunity to mention the Ocarina (#80). Remember the Troggs' '60s hit 'Wild Thing'? That blissfully gormless 3‑chord hymn to lust stunned the musical world of its day by dispensing with the then‑obligatory screaming guitar solo and substituting a rather sweet little ocarina melody. The Troggs were not known for their musical sophistication, so this choice of instrumentation remains one of the great mysteries of pop (see my book Reg Presley — Genius or Madman?). The ocarina, by the way, is a small spherical clay flute with a breathy, bird‑like tone.

Synth Miscellany (#81‑104)

Nestling curiously amongst the rest of the 'Synth Lead' family, the Calliope (#83) is actually the type of old‑fashioned organ found on a merry‑go‑round fairground ride [as heard on the theme tune to The Magic Roundabout and, in cut‑up collaged form, at the end of The Beatles' 'Being For The Benefit Of Mr Kite' — Ed]. On those delightful wheezing machines, the air supply to the pipes is automated by a system of punch cards, and we get the added bonus of mechanically struck drums, cymbals and bells, all playing in quantised time — perfect. Less entertainingly, Chiff (#84) is programmers' onomatopeic slang for a sharp breathy attack on the front of a synth sound. Dull. If you play a 'C' on Fifths (#87), you should also hear the 'G' above. While this makes for a quaint '70s lead sound, my experience is that fifths are much more fruitful if used subtly in chord pads — however, with every note automatically doubled a fifth above, you will need to simplify your chord voicings!

Ethnic — India, Japan & Middle East (#105‑112)

Moving dismissively along, I'm not even going to think about what the hell Goblins (#102) is meant to sound like. More imaginable by far is the Sitar (#105), whose melody strings are twangily enhanced by an underlying set of open 'chikari' strings. In Indian music, the sitar is often accompanied by the Tambura (supplied in an alternative bank on program #105 by one company). This wonderful instrument has four open strings tuned A1, D2, D2 (again) and D1, which are played gently and repetitiously in a fixed sequence to produce a constant background drone. A piece of silk or thread is inserted between the strings and the surface of the bridge to create the characteristic 'buzzing' resonance. Provided loops are made carefully, samples of the tambura can work very well.

After hearing me drone on about the tambura, I hope I may still be able to interest you in the alternative sound of the Gopichand or Gopi‑yantra — a 'doingy', one‑stringed Indian instrument, a bit like the South American Berimbau. Other options in this family are the Arabic Rabab (meaning 'bowed instrument'), and the Oud, originating from Iraq. This is the father of the Western lute, with a wooden, pear‑shaped body, a short fretless neck, and five pairs of unison tuned nylon strings, played traditionally with an eagle's quill plectrum!

Pulling chunks out of an eagle's arse merely to twang an oud seems bad enough, but one has to hope the RSPCA don't find out about the Shamisen (#107), as this Japanese long lute's square, box‑like wooden body is covered with dog or cat skin [once again, the sharp‑eyed among you may spot that the instrument pictured here is actually the Chinese take on the same instrument, but aside from the slightly different name, the San‑hsien, it's very similar — Ed]. The shamisen features a percussive playing technique in which a large plectrum hits both the string and skin at the same time, producing a drum‑like snap. Another Japanese offering, the Koto (#108), revisits earlier territory. Technically a 'long zither', this fabulous instrument is a six feet long narrow box with 13 silk strings stretched between two fixed bridges. Each string is bridged somewhere near the midway point, and plucked with plectrums on the thumb, middle and index fingers of the right hand. The left hand, meanwhile, presses the string behind the bridge to provide expressive bends and vibrato. An interesting alternative for #108 is the Kanun — this Turkish zither has 25 sets of triple gut or nylon strings, making it a 75‑string — eat your heart out, Roger McGuinn! If your kanun player tells you he needs to tune up, you should definitely take a lunch break.

The Kalimba (#109 — not 'Karimba', as it appears on some carelessly named synth patches, please) is an instrument of uniquely African origin, sometimes appearing under the name of Sansa, or, more daftly, Thumb Piano. It consists of a row of metal tines mounted on a resonating box. Played with the thumbs, these sound with a nice 'thunk' and a short, twangy sustain, making the kalimba a colourful and attractive pitched rhythm instrument (according to Miles Davis, it was the inspiration for the electric piano parts in his Bitches' Brew period). In its native habitat, the instrument appears in an array of unpredictable tunings, but the General MIDI version is equal‑tempered for western consumption.

The final 'ethnic' entry is the Shanai (#112), from North India (see below, left). A relative of the early English Shawm, the shanai is a double reed wind instrument with a flared brass bell at its bottom end. Its sound is loud and piercing, but extremely expressive. Though a little obscure, other variations in this slot include the Hichriki (a short Japanese bamboo pipe with a double reed) and the Pungi (Indian snake charmer's twin pipes — cobra not provided).

Re:percussion (#113‑120)

I don't know who proposed the name Tinkle Bell for GM program #113 — probably someone with small children. Tinkly bells are no great shakes, but happily, at least one company offers some exciting alternatives for this sound, in the form of the Bonang and Gender. These instruments from the Javanese gamelan (tuned percussion) ensemble offer rich, exotic metallic timbres. The bonang is a set of 14 or so small to medium gong‑chimes laid out in two rows on a wooden rack. Its sound is very rich in untempered overtones, for which reason I would advise against using bonang sounds to play chords — however, it makes a great, unusual timbre for a melodic rhythm line. The Javanese gender is an instrument with flattish metal bars suspended on strings above large bamboo or metal tube resonators, the whole thing constructed in an elaborately carved wooden case. Usually played with padded beaters, it has a pure, delicate sound, and is more intrinsically 'in‑tune' than the bonang. If you can find it in sampled form, the gender can be used to great effect as the basis for a soft, rhythmic keyboard patch.

Like many Latin percussion instruments, Agogo Bells (#114) are descended from African ancestors. The forerunners of these pairs of conical, black iron bells are the African Gankogwe, which share the agogos' design of a low and high bell (usually tuned about a fifth apart), and linked by a common stem. However, gankogwe are larger, unpolished and industrial‑looking.

We conclude with a resounding thud on the Taiko (#117). Taiko (which becomes '‑daiko' after a prefix), is simply the main Japanese word for drum. The construction of these instruments is simple; cowhide heads are stretched and nailed over each end of a wooden shell with rows of brass tacks, and the drum is played on one head only with thick sticks. Variants on the taiko include the Odaiko and Matsuridaiko ('festival drum'). Such faintly ominous sounds can be used effectively in sparse atmospheric music, bridging the gap between a rock kick's dry thud and the pomp of an orchestral bass drum.

Should you desire more standardisation in your life, the entire General MIDI spec is available for download from [er, Dave... I think you mean‑midi/gm/gm1sound.htm — Ed].

Table 1 — GM Instrument Family

(1‑8) PIANO

(9‑16) CHROMATIC (ie.tuned)


(17‑24) ORGAN

(25‑32) GUITAR

(33‑40) BASS

(41‑48) STRINGS

(49‑56) ENSEMBLE

(57‑64) BRASS

(65‑72) REED

(73‑80) PIPE

(81‑88) SYNTLEAD

(89‑96) SYNTPAD


(105‑112) ETHNIC

(113‑120) PERCUSSIVE


Corporate Cooperation: GM * GS * XG

Japanese companies are by nature competitive rather than cooperative, and initially viewed even the idea of MIDI itself with suspicion. General MIDI, too, seems to have been grudgingly accepted, but cracks appeared quite rapidly in the accord: Roland have their own variant called GS, and Yamaha hit back with XG. Both of these unmemorably named systems set out to add multiple banks of sounds to the basic GM set, thus undermining its very raison d'être. On the other hand, you do get more programs — for each basic GM sound, several variations are available in the XG and GS sets, often different instruments or regional variations that work on the same principle as the basic sound.

Playing Tip 1 — Tuned Percussion

Though the playing ranges of the marimba and xylophone overlap to a considerable degree, you can combine both into a single keyboard patch by mapping them onto your keys as shown in the diagram here. The split point may be varied according to taste, but being the higher‑pitched of the two, the xylophone usually sounds more convincing in the top register. In real life, a marimba's lowest note is A1, but a further octave of deep bass notes (down to A0) is available from the mighty bass marimba.

Also shown is the typical range of a 14‑note balafon. If authenticity is your goal, remember that traditional African music uses no chords, has a limited range of notes (C, D, E, G and A will suffice) and does not change key!

Playing Tip 2 — The Shakuhachi

My occasional musical collaborator and ethnic wind maestro Dirk Campbell [see SOS November 1997 — Ed] has this advice to pass on: "The shakuhachi is a popular Japanese end‑blown flute which is well known to Western players through its inclusion as a sample in keyboards. The basic sound is quite sweet, with more breathiness but less body than a Western flute and a similar range — middle C and two and a half octaves up. The sample everyone knows is a sound like a yodel which is produced by two grace notes, first a fourth above, then a tone below the main note." Peter Gabriel fans will remember this evocative (though now over‑used) sound in the intro to 'Sledgehammer'. Unfortunately, such grace‑note effects can only be convincingly achieved on keyboards using performance samples, which lie beyond the scope of General MIDI.

Playing Tip 3 — Sitars

Would‑be sitar heroes please note: If you want to realistically emulate the sound of this instrument from a keyboard, remember that chords are not used, and the melody strings can be bent up by as much as a fifth! The judicious use of pitch bends (both upwards, then downwards) will do a lot to simulate a real sitar performance, to which end you may have to set the pitch‑bend range on your sitar patch to more than the standard two semitones.

Playing Tip 4 — Wind Instruments

With the exception of Pan Flute (#76, also known as Panpipes, and shown right), none of the solo wind instruments in the General MIDI list are capable of playing more than one note at a time, and even the panpipe players try to avoid it!

With this in mind, try programming your GM unit's solo winds to play in mono mode — this eliminates any audible overlap between notes, thus producing a more authentic wind sound. If you're using a sequencer, the same effect can be achieved by painstakingly editing note lengths to remove any overlap. This takes a lot longer, but helps to conserve the polyphony of your GM instrument as well as improving the realism of the parts you play.

Playing Tip 5 — Modulation & Vibrato

Once your hand lights on your MIDI keyboard's modulation wheel, it is tempting to whack it up to maximum at every opportunity. Unfortunately, this tends to produce an unpleasant queasy wobble which will soon make your audience feel seasick. Learn to moderate your pitch modulation: reserve it for solo instruments, and even then only in very small doses, perhaps introduced subtly after the note has first sounded (this can even be programmed to occur automatically). If you find that even a tiny movement of the mod wheel produces a huge amount of pitch wobble, you should reprogram the patch in question with a reduced 'wheel‑to‑pitch‑mod' response. Programmers often set the vibrato rate too fast, so be prepared to edit that parameter too!

Other than for comic effect, I see little point in using pitch modulation on percussion sounds, be they pitched or unpitched. However, the Vibraphone (#12) will benefit from a little amplitude modulation, a more subtle type of vibrato which mimics the sound of the real vibes' motor‑driven vibrato. If you can work out how to apply this, by all means try it on other instruments (especially wind and brass), as it varies the unnatural constancy of a sample's looped sustain without messing with its pitch.

A Big Thanks To...

SOS would like to thank Henry Stobart and the Faculty of Music at Cambridge University for the pictures of the gamelan instruments and panpipes.

For the opportunity to take pictures of the oud, yang chin, shakuhachi, sitar, tambura, san‑hsien, kalimba, shanai, and taiko, we are indebted to Mr and Mrs Ray Man of the Ray Man Ethnic Musical Instrument shop in Chalk Farm Road, London (+44 (0)20 7692 6261). If this article has piqued your curiosity and you'd like to see some of the real instruments mentioned, check out or call in at the shop.