Audience members will be invited to pay what they like for what they hear at an upcoming Halle Orchestra concert.
Priceless Classics on 6 September will see the orchestra play 10 short pieces at Manchester's Bridgewater Hall.
Holders of pre-booked free tickets will then be able to pay whatever they think the event was worth.
Chief executive John Summers said it would let new audiences "experience the Halle and enjoy some incredible music, but on their own terms".
"We wanted to do an event which would bring in a new audience," he told the BBC. "People who thought classical music was not for them or had never been to a concert hall and were kind of scared by the whole rigmarole."
"We are doing 10 pieces which actually start in 1700 and go through to the present day - roughly a piece every 35 years.
"We are specifically timing them so if you wanted to miss piece three and come back for piece four you'd know exactly when piece four starts.
"You can have a drink. You can go to the loo. The whole point it that people don't need to feel constrained by the normal concert etiquette.
"If they want to clap they can clap. We are also encouraging the orchestra to walk off the platform."
Programmes will be distributed free at the concert, which will feature selections from Bach, Mozart and eight other composers spanning three centuries of music.
The concert will be conducted by Stephen Bell, who has spent the last two years as associate conductor of the Halle's Pops Series.
Tickets would normally start at £10, with a maximum price of around £40.