Some of the top composers of contemporary music, including John Adams, John Corigliano and Richard Prior, have issued a statement in support of the locked-out musicians of the Atlanta Symphony Orchestra.

"We unanimously encourage those involved in its management, board and funders to do whatever necessary to keep this great orchestra vital and thriving," the 14 composers wrote. "The ASO must not be allowed to degrade, piecemeal, into a second-class entity."

Their letter was issued on Thursday, on what was to have been the opening night of the ASO’s 70th anniversary season.

ASO and Woodruff Arts Center management locked out musicians for the second time in as many years on Sept. 7, when the ASO administration and the musicians could not reach accord on a new collective bargaining agreement when the previous one expired.

The two sides have not returned to the negotiating table since the lockout, and the musicians are marking what would have been the season-opening with “A Deafening Silence,” a silent protest, at 7:30 p.m. Thursday across Peachtree Street from the Midtown arts center.

"We are appalled to see the orchestra's supremely talented players locked out from playing their concerts while at the same time being asked to accept painful salary cuts and submitting to the reduction in the size and quality of their ensemble," the composers added in the statement. "Artistically the Atlanta Symphony is one of the few in the country with a clear vision and proven track record of balancing the creation of new works with the preservation of the old."

ASO music director Robert Spano is well-known for his support of contemporary music. During Spano's tenure starting in 2001, he and the ASO have performed nearly 100 contemporary works (composed since 1950), including seven ASO-commissioned world premieres, two additional world premieres and one U.S. premiere, according to the orchestra's web site.

Under Spano's guidance the ASO established the Atlanta School of Composers to nurture, commission and record contemporary music through multi-year partnerships with emerging composers.

Five Atlanta School of Composers members added their names to Thursday's statement: Jennifer Higdon, Christopher Theofanidis, Osvaldo Golijov, Michael Gandolfi and Adam Schoenberg.

Five of Spano’s recordings with the ASO have won eight Grammy Awards, including Higdon’s "City Scape," Golijov’s "Ainadamar" and a disc that features Theofanidis’ "The Here and Now."

The orchestra has had deficits for 12 consecutive years, including a $2 million one in fiscal 2014, and management said it could no longer borrow against interest from its declining endowment. They sought further concessions from the musicians, who agreed to a 14 percent pay cut on average in 2012, when the orchestra's ranks were reduced from 95 to 88 full-time musicians.

The entire text of the composers statement follows:

We write as a group of American composers in loud support of the Atlanta Symphony Orchestra and its unique and important place in American concert music. We unanimously encourage those involved in its management, board and funders to do whatever necessary to keep this great orchestra vital and thriving. The ASO must not be allowed to degrade, piecemeal, into a second-class entity.

We are appalled to see the orchestra's supremely talented players locked out from playing their concerts while at the same time being asked to accept painful salary cuts and submitting to the reduction in the size and quality of their ensemble. Artistically the Atlanta Symphony is one of the few in the country with a clear vision and proven track record of balancing the creation of new works with the preservation of the old.

The people of Atlanta cannot afford to preside over the slow, remorseless downgrading of its most important artistic institution.

The Woodruff Center and the city of Atlanta have a priceless jewel in the Atlanta Symphony, and they have a responsibility to preserve it. Its loss would be incalculable.