“I’M NOT sure why,” said Sigmund Freud, not usually one for ambivalence, “but trombones make me very uncomfortable.”

Poor old trombones; there are so many quips. The advice purportedly given by Richard Strauss to young conductors: “Never look at the trombones – it only encourages them.” The devilish glint in the pen of critic-playwright George Bernard Shaw, who wrote that “a taste for brass instruments is hereditary. My father destroyed his domestic peace by immoderate indulgence in the trombone. My uncle played the ophicleide – very nicely, I must admit – for years, and then perished by his own hand. Some day I shall buy a trombone myself…”

By rights the trombone should be the noblest of instruments. It was revered by 16th century Venetians church composers for its antiphonal gloriousness, by Mozart for girth and glow in his requiem and late operas. The Canadian composer Murray Schafer turned to trombones – 12 of them crooning across water at dusk and dawn – to instil calm and contemplation in his Music for Wilderness Lake. There were the trombone legends of the jazz age who kick-started a renaissance, reminded the world what the instrument could do. “My greatest teacher was not a vocal coach,” admitted Frank Sinatra, “not the work of other singers, but the way Tommy Dorsey breathed and phrased on the trombone.”

This weekend is trombone weekend: first (and possibly last) event of its kind in Scotland, hosted by the BBC Scottish Symphony Orchestra with a programme of trombone-related music, workshops and competitions. The orchestra’s excellent principal trombonist Simon Johnson features, as does the blazingly virtuosic Austrian septet Mnozil Brass. And if there’s any one trombonist who has pioneered the instrument as a solo beast, it is Christian Lindberg: Swedish composer, conductor and uninhibitedly flamboyant performer. He’ll be conducting Wagner (Overture to the Mastersingers of Nuremberg) and Rossini (Overture to The Thieving Magpie) as well as playing and directing Jan Sandström’s Echoes of Eternity (a concerto for two trombones and orchestra) and a piece of his own called The Waves of Wollongong.

Is there a broader timeliness to all this? For Lindberg, championing an underdog instrument is a matter of subversive social principles as much as righting musical wrongs. “Maybe if I’d been in a hip young orchestra I would never have become a soloist,” he tells me (or rather yells at me: when I call he is driving into Stockholm, shouting into his speaker phone and punctuating the conversation with cheerful cries of “where the hell am I?!”). As a teenager Lindberg was enthralled by dixieland trombonist Jack Teagarden; he loved his flair. His own first job was in the orchestra of the Royal Swedish Opera. He was 19, the orchestra was conservative. “We did the world premiere of Ligeti’s Le Grand Macabre,” he recalls. “I loved it but everyone else hated it. There were 12 performances planned but they cancelled eight of them. Can you imagine? Cancelling Ligeti?!” No, but sadly history has taught us to fathom such philistinism.

It was the kind of attitude that could get a bright young musician down, he says, especially one who plays the trombone. “Because they all believed in this kind of violin supremacy. Violin first, then other string instruments, then woodwind. Trombones came pretty far down the list.” When Lindberg played his first concerto, the conductor outright objected. “He said he would go as low as a French horn but no lower, and he wasn’t talking about pitch! When I started playing, he stopped after two bars and put his hands over his ears… He made me stand at the other side of the stage.”

That was 1986, and things have generally changed in favour of our t-bone friends. Lindberg has had no small part in that resurgence. He has premiered more than 300 new works for the instrument, more than 100 of which are concertos, and has solicited new trombone repertoire from the likes of Berio, Takemitsu, Schnittke, Xenakis and Arvo Part. The standard of trombone playing has improved enormously since the 1980s, he says. “But I’m a bit disappointed that nobody has been brave enough to follow my path. I took a big risk when I left the orchestra and became a soloist. I have had plenty of really brilliant students, but you cannot play it safe. They keep their security in orchestras. Nobody has dared to jump the nest.” Granted, Lindberg tops up his own tromboning with conducting and composing, but that seems more to amuse his hyperactive creative side than for any want of concerto engagements.

In The Waves of Wollongong, his piece for nine trombones and orchestra which we will hear in Glasgow, the influences come from all over the place. “There was a crime that was never solved,” he starts. “A murder. At the same time there was a friend of mine who had cancer. He had a dangerous surgery while I was writing, and in a naive way I guess I was trying to throw away the cancer with the music I was writing. Turned out he was OK. And I was on tour with New Zealand Symphony. The nature was incredible. This place, the waves. I imagined each trombone being a wave going over the whole orchestra.”

That Lindberg’s compositional inspiration crash-lands from all directions does not surprise me. His aesthetic philosophy? Simple, he states on his website: “I do not write in any style whatsoever! I just listen to what my brain and my soul tell me, and what I hear, I simply put down on paper. To say anything more about my work would be pretentious nonsense.” The most important thing, he adds on the phone, “is that I am completely free. To listen to my inside, not to be dictated to from the outside. What’s important is that whatever comes out, good or bad, it comes from me. That’s the essence of the piece.”

Yet when it comes to conducting, he says, “it’s the opposite. Working as a conductor with an orchestra… then I’m very structured. Pedantic. Then it’s important to follow the intention of the score. Follow the original tempo markings. Then I’m just someone who is expressing what someone else has created.

"Thing is,” he adds, and I can now hear him pulling into Stockholm, city noises mixing with the traffic, distraction creeping into his conversation as he tries to work out his route, "thing is, as a person I’m extremely intuitive and emotional and vibrant and extrovert. So if I don’t hold myself strictly as a conductor I would go berserk.” He lets out a huge laugh. “In rehearsals anyway. In performance, anything goes!”

The BBCSSO’s Trombone Weekend runs from tomorrow and Friday at Glasgow City Halls, and to Sunday in partnership with the Royal Conservatoire of Scotland.