The band played on

If you're out on the parade routes today, or just watching them on TV, cock the head sideways and tune into the melodies, if you can hear them at all beneath the clattering drum tattoos.

Although now largely replaced by snare and bass drums, the Lambeg is the iconic Orange instrument. It evolved over the 1800s from the European military Long Drum, to make the loudest possible boom. It's now a big, two-sided oak and sheep-skin drum, up to 40lb in weight, and over three feet in diameter. Lashed by malacca canes, it produces 120 decibels, the equivalent of a light aircraft or pneumatic drill.

The Lambeg has been largely confined to counties Antrim, Down, Armagh and Tyrone, and it was often painted with Williamite iconography and names such as Cock of the North or The Orange Conqueror. Some fine examples remain: one from 1870 in the Moira Orange Lodge number 39, and even one from 1849 in Belfast made by a man called Walsh.

By the 1870s, the Lambeg had become a solo, competitive instrument. Traditionally, two rival drummers face each other "hoop to hoop", and batter out set "tunes" for hours on end, until one deafens or knocks the other one off his rhythm. As there is no manual for, or standardisation of, Lambeg playing, it's very much an oral tradition, taught with such mnemonics as "there's a pub, there's a pub, on the Lambeg Road . . ."

Also nearing extinction is the fife, a small, six-hole wooden flute, played with cross fingering up in the third octave. The fife has given way to the six-key flutes played by "melody bands", which hammer out tunes in unison. This is the style of many "Kick the Pope" or "Blood and Thunder" bands associated with the paramilitaries.

The Irish Traditional Music Archive in Dublin holds cassettes by the Silver Skull Flute Band, the Kings of Kick and the Bitter Orange Singers, performing poisonous little gems such as The Ballad of Michael Stone and The Piggery where the Beggars Play. Musicians note how many Orange marches originate from Irish dance tunes. Reels were often "dropped" into hornpipe 4/4 time, while jigs were squared off into march time from 6/8 to 2/4.

Gary Hastings, a Church of Ireland clergyman from Belfast and a fine flute-player, is one of the few commentators on Orange music. "The marching band repertoires are very eclectic, from `party tunes' like Derry Walls or The Sash, to adapted dance tunes. The classic crossover is the Boyne Water which is exactly the same tune as Ros Catha a na Mumhan, the Battle Cry of Munster.

Or they latch onto popular stuff, like the tune to Coronation Street. I remember once hearing Puppet on a String. And my grand-da had a story - he played in the Ravenhill flute band - about going down to Dublin to the Eucharistic conference in 1932. They all won big medals in Irish for playing I Scream, You Scream, We all Scream for Ice-Cream . . .

"There's a strange symbiosis between the band culture and Orangeism. Orangeism nucleated them, but the band culture exists in its own right. Some bands have gone paramilitary, because Orangeism is starting to look old-fashioned, and the whole loyalist thing is taking over, with the boys in the sunglasses and black berets.

"But it's a strongly developing tradition. And unlike traditional dance music, which is getting pulled around by commercialism, it's being moulded by politics and the surrounding culture, and whatever way the boys are thinking at the time." Seventy-two-year-old John Kennedy, a Protestant, is a traditional singer, whistler and yarn-spinner from Cullybackey, near Ballymena, a DUP heartland. Between 1945 and 1975 he fifed to the Lambeg, and between 1973 and 1998, he taught music for Comhaltas Ceoltoiri hEireann in Portglenone and Dunloy. "Away back long ago, it used to be all drums and fifes, even before my time, and then the bands come in, but there was still a lot of them held onto the Lambegs, and it used to be a necessity that they had at least one fife.

"I firmly believe that the fifing tunes are all Irish dance tunes - jigs, reels and hornpipes - it's all bred of the one thing, and it's quite easy heard." To prove his point, Kennedy diddles a fifing reel called the Green Fields of America, originally the song Pretty Molly Brallaghan, speeded up.

"It was all accordion players when I was growing up, and there were a terrible lot of Irish dance music and very good fiddlers in nearly all the districts. Actually they kept it going when some of the nationalist areas wasn't playing so much of it."

Kennedy learned music from Willie Nicholl from Killyless, himself taught by the one-eyed Jock Lecky, who made Lambegs for both the Orange Order and the Ancient Order of Hibernians.

For today's respectable bands, the World Championships are held in Belfast in the Ulster Hall by the Northern Ireland Bands Association (NIBA), which has 80 affiliated members. Pipe bands, led by the Field Marshall Montgomery Pipe Band, come under the Royal Scottish Pipe Bands Association, but the NIBA oversees Ulster flute bands, accordion, brass, and military bands.

Edward McNally, conductor of Portadown's Corcrain Flute Band, which dates back to the 19th century, says: "Some melody bands give us a bad name with the way they carry on. But we've opened a section for them, where they can play a two- or three- or even four-part harmony, and the competitions are well attended now. They're beginning to realise they've got to play good music. Sometimes they have up to 12 sidedrums and two bass drums, and the flutes can hardly be heard over the banging and whacking."

He explains that these bands often play the old system of small wooden or aluminium six-key flutes in Bb, F, Eb or Ab. "These were specially made by Ruddel & Carte and Boosey & Hawkes, high-pitched flutes for playing out on the road."

In 1963, a Scottish band from Motherwell "had the audacity" to win the World Championship with 18 concert flutes - "ordinary flutes you could buy over the counter" - and Ulster gradually switched to the Boehm system. The Corcrain Flute Band, which plays concerts throughout Northern Ireland, now uses piccolos in top C, G-treble flutes, C concert flutes, G alto flute, a C bass, and a double-G alto bass - but some bands stretch to a contrabass.

The competitions involve an invited adjudicator, "usually a military man from England", and bizarrely, he is concealed inside a box. "It's real cut-throat stuff here," laughs McNally. "But that's the tradition. The whole thing began away back when the NIBA was formed in the late 1800s, when there was a lot of cheating going on, so they wanted an unbiased adjudicator, who could only listen to the bands."

McNally, a self-taught musician who scores music for the bands, complains that the "Blood and Thunder" bands get all the attention. "The centre of Portadown now is a very militant place. We actually practise in the hall where the Drumcree people are based, but we've nothing to do with them, we've never even been to Drumcree. Many years ago, the band did walk down the Garvaghy Road, there was never any problem, the people there knew us and worked with us, and they waved at us, but that was before the Troubles . . .

"I'm not in the Orange, I'm not that way inclined. I just love music. Most of the good bands in Belfast won't parade on the 12th now. We do, even though we're very small on the road, because we get a few hundred pounds for it, and we need that to buy new flutes.

What about the old Orange repertoire, song-tunes such as Th'ould Orange Flute, Lilliburlero, or Dolly's Brae, the Orange version of the contentious 1849 parade which resulted in the massacre of at least 30 Catholics? "None of the top bands play the `party tunes' any more, not even The Sash, because we don't want to offend people. We've a march that contains Derry's Walls and Slopes of the Boyne, but we seldom play it.

"An awful lot of these `Kick the Pope' bands have sprung up purely because of the Troubles. And some of them would have solicitors and even doctors in them, because they love playing the flute. There's only two of them in Portadown, the Portadown True Blues and Portadown Defenders. They have big bass drums, and they always end up bursting the skins, but they've always got spares for them."

Although he only sees the occasional Lambeg now, he grew up with drumming contests in Richhill, Co Armagh. "Quite a lot of people still attend them - even people of the Catholic persuasion. They're held in out-of-the-way places in the countryside - so long as the pub is within walking distance.

"They usually start at half-six or seven on a Saturday night and go all-out till midnight, and people get very excited, and if the adjudicator lifts his cap one way or another to indicate who he thinks is the best, he could end up in a drain somewhere. He certainly usually got a painful kick for his sins . . ."