Recording artists such as Sir Paul McCartney and U2 have backed a call for an extension of copyright on sound recordings from 50 years to 95 years.
The advert is supported by the likes of Katie Melua and Roger Waters
An advert in the Financial Times has been signed by over 4,500 artists, from session musicians to Peter Gabriel.
It follows the government-commissioned Gowers Report, which recommended the protection should not be extended.
The British Phonographic Industry has campaigned for parity with the US, which has a 95-year limit.
Performers and writers earn royalties through airplay and sales of their songs.
Writers have copyright for their lifetime plus 70 years, but it is the rights to a particular recording of a song which is at the centre of the current debate.
BBC media correspondent Torin Douglas said the advert, which demands "fair play for musicians", was a last-ditch attempt by thousands of musicians to win a battle they seemed to have lost.
Signatories include Sir Cliff Richard and Sir Simon Rattle as well as little-known session singers and orchestral players.
They say it is not just superstars who would benefit from an extension but performers at all levels.
In the US, copyright protection was extended for sound recordings from 50 years to 95 years in 1998.
Sir Cliff Richard's earliest recordings will soon be affected
Andrew Gowers, the former Financial Times editor who led the review, said a change would put up costs while giving little public benefit.
A spokesman for the Open Rights Group, which campaigns for greater digital rights, said: "The big music firms have done a good job of persuading some artists to sign up to this but anyone who reads the Gowers review will see it demolishes the arguments for extension.
"An awful lot of content creators are not represented by this and recognise an extension will do nothing for creativity and nothing for the public."
Although the government could choose to ignore the review, this would bring it into conflict with the European Union, which is already working to harmonise intellectual property laws on the 50 year limit.
The report, which looks at modernising UK copyright laws for the digital age, has also caused controversy with another of its recommendations - that private users should be allowed to copy music from a CD to their MP3 player.
The UK's independent record labels said they feared it would "open the floodgates" to uncontrolled private copying, and sharing from person to person