A small but growing niche in the soundtrack market is the commercial release of original recordings of classic film scores. But it’s only possible in rare instances when the studios have been savvy enough to keep and properly preserve the originals.

Music from great old 20th-Century Fox movies (through Varese Sarabande), MGM and Warner Bros. pictures (via Turner’s deal with Rhino) and Disney animated films (its own Walt Disney Records) is finding its way onto compact disc.

Varese has the most ambitious program, with plans for 16 to 20 albums of Fox music over the next three years, according to executive producer Bruce Kimmel.

Jerry Goldsmith’s strange, groundbreaking score for “Planet of the Apes” and Bernard Herrmann’s romantic classic “The Ghost and Mrs. Muir” are among Varese’s first releases in the “Fox Classics” series, with future titles expected to range from David Raksin’s “Forever Amber” to song compilations featuring Shirley Temple and Marilyn Monroe.

Unfortunately, not every desirable title will be available because the quality of the original elements — the film that the music was first recorded on — varies wildly, according to producer Nick Redman. Redman launched the Fox series in 1993 (when the studio had its own record label) with such memorable scores as “The Day the Earth Stood Still,” “Laura” and “How Green Was My Valley.”

From the ’30s through the early ’50s, music was recorded onto optical film; from the ’50s through the early ’70s, onto magnetic film; and after that, on tape. “Many of the optical film elements that were in Fox’s possession were deemed a fire hazard (and destroyed), but some of those elements were transferred onto tape as part of an archival program begun at Fox in the 1980s,” notes Redman.

The ’50s-to-’70s material on “mag” varies in quality both because of the film stock used (’60s hasn’t fared as well as ’50s, for example) and the conditions under which it was stored. “We recently restored the entire score to ‘The Sound of Music,’ which was in horrible shape,” Redman says. “It’s arguable that were it to have been left for another year or two, it would have been impossible. The mag literally decomposed as it went through the machine.”

Producer Marilee Bradford faced similar problems when, during her tenure as director of soundtracks A&R at Rhino Records, she produced newly restored, expanded editions of “The Wizard of Oz,” “Ben-Hur,” “Doctor Zhivago” and other MGM scores.

“One might assume that music masters are well-preserved if they are stored in a temperature-controlled environment, properly inventoried and sealed in airtight cans. This is simply not the case,” she explains. “A variety of audio formats from days past were created from chemical compounds that often fail the test of time or disintegrate from exposure to movement, air, moisture, or even dirt and oil from recording heads. Age is only one small factor to consider.”

When Bradford set out to do an album of Bernard Herrmann’s 1959 “North by Northwest” score, she found that the tape of his most important orchestral sessions had “deteriorated almost beyond use. We had precisely one pass to transfer this tape to a digital format before it fell apart in our hands.”

Producer George Feltenstein culled the tracks for Rhino’s new release of Max Steiner’s “Casablanca” score from several sources, including newly discovered 35mm nitrate optical film of the 1942 recording sessions that had been “stashed” years ago in the Warner Bros. vaults; acetate discs from Steiner’s estate housed at Utah’s Brigham Young University; and the film itself.

Unfortunately, much of the Warner Bros. music has been lost over the years. That’s not the case with the MGM library, however. Feltenstein says: “We have 95 percent of all the music that was ever recorded at the studio.” And last year Turner began transferring to both digital and analog tape “every can of magnetic music that’s in the vaults. So even if we don’t have an album planned, it’s all being protected.”

One might think that Disney, with its asset-protection corporate mentality and well-known musical legacy, would have retained all its original recordings. Not so, reports producer Randy Thornton, who has worked on all 10 classic Disney soundtrack re-releases since “Mary Poppins” in 1989.

“In the ’50s, a lot of these original elements — music-only tracks, vocal tracks, separated sound effects tracks — were destroyed,” he says. “They had the music and effects tracks mixed for all the foreign markets, and the composite with the dialogue, music and effects for the English-speaking countries, so (studio execs) didn’t think they needed any of these elements any more.”

Luckily, Thornton and similarly archival-minded people on the Disney lot saved bits and pieces over the years. For example, unlabeled cans of optical film — the music-only tracks for 1940′s “Pinocchio” — were discovered in a corner of a Disney vault, enabling Thornton to fully restore the soundtrack for a 1992 release. The 1993 “Snow White” CD contains more than 1,000 separate musical edits because it was assembled from seven different sources.

Studio execs are just now awakening to the value of their music libraries. They should be preserved, says Redman, “because it’s practical. They are a part of the studio’s assets. It behooves any studio to have these assets prepared in a digital format that will enable them to use it, or adapt the material to forthcoming technologies.”

Restoration costs, adds Bradford, “can often be naturally absorbed as production expenses for commercially viable soundtrack albums. With proper marketing and distribution, it’s a win-win situation for the studios: profitable product and a fully restored master tape library.”

Independent producers have approached execs at Paramount, Universal and Republic about tapping into their music libraries for soundtrack CDs, but no deals have as yet been struck.

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