It was the demonstration that had everything. Talented musicians playing Wagner and Bizet and actors handing out leaflets.

It was one that politicians of all parties turned up to, but it didn't have the real stars, David Tennant of Doctor Who or James McAvoy of The Last King of Scotland, because as it was pointed out they were too busy working all over the world.

And that was the point, said organisers. Allow the Royal Scottish Academy of Music and Drama to decline and Scotland loses global cultural clout.

The issues had been raised inside that chamber by Glasgow Kelvin MSP Pauline McNeill, demanding special action to save RSAMD from disaster. The problem was that those speaking for the institution outside were clear that it was a problem dating back to 1992 that had not been addressed by governments since then.

That was the year when the funding council decided that our future James MacMillans or Evelyn Glennies would receive full "conservatoire" funding as emergent musicians, but our future James McEvoys or David Tennants would be categorised with hospitality workers and funded at barely half the rate.

Waiters versus Oscar winners resulted in a generation of underfunding for RSAMD, where the institution equalised the £12,000 per head music students received with the £7000 paid for drama students and soldiered on. Now a pay award for lecturers threatens a £600,000 funding crisis next year as all the reserves have been used up.

Barry McAleer, student union president, said: "We have survived 16 years of underfunding because of cross-subsidy.

"Without that subsidy we would never have had Tom Conti, James McAvoy, Alan Cumming, John Hannah or Robert Carlyle."

Chris Wlliot, graduate member of the Student Union, said: "We have produced such successful graduates that they are in Los Angeles, London and Italy today, but if this institution did not exist then James McAvoy would not have starred in The Last King of Scotland, the Black Watch would not have had a cast, and River City would be a wasteland."

Tom Conti sent a message of support saying: "If I had not got in, I would probably not have a career as an actor." In similar vein, John Hannah said: "It's true that these cuts are being forced on the academy when what we need is investment in talent."