Video report by ITV News north of England correspondent Martin Geissler.
Claims of sex abuse by music teachers are spreading beyond the Chetham's music school in Manchester where they began, ITV News has been told.
Choirmaster Michael Brewer will be sentenced tomorrow after being convicted of five indecent assault charges.
Since then more alleged victims have contacted police.
Over the years Chetham's has won international acclaim for taking virtuoso young musicians and turning them into stars.
Prompted by Brewer's trial, dozens of once-aspiring young musicians who studied at schools up and down the country have started to tell their stories.
And a petition demanding an inquiry gathered a thousand signatures within a week, with many respondents claiming they had also been abused.
"The sheer scale of the allegations was extremely shocking," said pianist Ian Pace, who started the petition.
The claims paint a picture of widespread abuse across a range of schools involving dozens of staff from the 1960s to the 1990s.
Greater Manchester Police described the complaints from their area as "a large scale investigation."
ITV News understands as many as 10 former tutors at Chetham's are already under investigation.
Chetham's say their staff and working practices have changed over recent years and they are determined to learn the lessons of the past.