With newfound support by such heavyweight film composers as Hans Zimmer, James Newton Howard, Thomas Newman, Danny Elfman and Carter Burwell bolstering the effort, the Screen Actors Guild has joined the Writers Guild of America in backing the push by composers and lyricists to unionize by aligning with Teamsters Local 399.

About 200 tunesmiths turned out for an organizational meeting Monday night at the WGA theater in Beverly Hills, where organizers also confirmed that — if they do unionize and ultimately get to the bargaining table with the Alliance of Motion Picture and Television Producers — they would seek only medical and pension benefits and not attempt to set minimums or bargain for working conditions.

“What we do is under siege,” composer Mike Post told the crowd. “The thing we do for a living is being degraded, disrespected and devalued. Technology has collided with budget crunch.”

However, despite widespread concerns that wages have plummeted and time frames to write and record music have shrunk to the breaking point, the “Law & Order” composer said that negotiations with producers should be “limited to something we can all agree on,” meaning benefits alone.

Several speakers noted that composers and songwriters are the only creatives left in the business who have no union protections. (The Composers & Lyricists Guild of America, which existed from 1954 to 1982, once provided benefits but was disbanded after a decade of battling the networks and studios over thorny music-rights issues.)

Actor James Cromwell read the SAG letter of support, and WGA West exec director David Young reiterated the WGA backing announced last week by WGA West president John Wells. “Writers consider you our peers and collaborators,” he said, citing “deteriorating conditions” for composers throughout the industry.

In addition to Zimmer and company, high-profile composers and songwriters who have also signed on as supporters include Quincy Jones, Randy Newman, John Debney, John Powell, Keb Mo’ and Diane Warren. TV producers Steven Bochco and Dick Wolf have pledged support, as have directors Ron Howard and Ed Zwick.

Teamsters business agent Steve Dayan, who is spearheading the organizational effort, made several points in response to audience questions, including: composers can work non-union jobs even if they are union members; videogame composers will not, at first, be included, unless they also do TV and film work (“that will come in time,” he said); aspects of the Teamsters’ successful 2006 organization of casting directors and subsequent contracts with AMPTP will serve as models for an initial composers’ contract; they would prefer to avoid any process involving the National Labor Relations Board, which twice ruled against composers and lyricists in the 1980s attempts to re-unionize.

Rick Marvin (“Six Feet Under”) indicated that many of his fellow composers feared losing employment because studios and networks often demand that they work non-union and not employ union musicians. But, he said, when he tells execs, agents and showrunners that they only want benefits, most have said “that’s fair, that’s what everybody else gets.”

Ray Colcord (“Boy Meets World”) said he doesn’t want his occupation “turned into a hobby” due to the declining level of respect for music in films and TV. Without a union, he said, “we’ll surrender our way to victory. It didn’t work for Neville Chamberlain and it’s not going to work for us.”

The American Federation of Musicians, which already negotiates with AMPTP, covers many aspects of music-making including orchestration, conducting and performing but not the act of composition. The Recording Musicians Association, a “conference” within the AFM, has expressed its support for composers. The AFM has not yet formally indicated where it stands, nor has the Society of Composers & Lyricists, a support group formed after the demise of the CLGA.