Swansea and Neath Port Talbot to 'go it alone' on music service
About 80 musicians staged a silent protest at Swansea's Guildhall after councillors agreed to end the music partnership with Neath Port Talbot.
Swansea council's cabinet agreed a music service for Swansea would remain and joint orchestras would continue.
It said this would give the area the chance to develop a sustainable and professionally-organised service.
But campaigners said the system of operating from a large pool of talent meant access to "genuine expertise".
A Swansea schools' music service will be launched in September to replace West Glamorgan Music Service.
The council had originally proposed removing its music service subsidy by April but agreed to continue with a reduced subsidy for another year while a service review is undertaken.
Parent and former student Rowland Gibbs said: "The current working practice is we have expertise shared across a large pool that means you get genuine expertise.
"The minute you take the pool of teachers down, the expertise is diluted."
Jen Raynor, cabinet member for education, said: "By continuing with it [the service] in its current state we would risk losing it forever which no-one wants.
"We will be improving music offers to schools and families who are unable to fund private tuition."