We brought you the details and track listings for James Gunn's Guardians of the Galaxy soundtrack about a week ago, but some new quotes from the director reveal just how important that music was both on set and within the film itself.  In addition to the twelve classic songs found on the soundtrack, Tyler Bates' score was equally important, as Gunn asked him to finish some of the tracks before principal photography even began in order to use it on set to establish emotional beats.

The film stars Chris Pratt, Dave Bautista, Zoe Saldana, Lee Pace, Benicio Del Toro, Glenn Close, Karen Gillan, Michael Rooker, Djimon Hounson, John C. Reilly, and the voices of Bradley Cooper and Vin Diesel.  The Guardians of the Galaxy soundtrack will be released on July 29th; click here to pre-order.  The film will be released in 3D on August 1st.  Hit the jump for more on music's role in the latest Marvel movie.

The quotes from Gunn regarding the Guardians of the Galaxy soundtrack and score come courtesy of Marvel themselves.  As for the use of music in the film, Gunn's reveal of its importance may be a bit spoilery, so you might want to skip it.  Otherwise, highlight the following quote:

“One of the main story points in the movie is that Quill has this compilation tape [Awesome Mix Vol. 1] that he got from his mother before she died that she made for him. It was of songs that she loved, all songs from the 1970s, and that’s the only thing he has left of his mother and that’s the only thing he has left of his home on Earth. He uses that as a connection to his past and to the sadness that he feels of having left all that and lost all that.”

Less spoilery is Gunn's use of Bates' score during filming of the movie itself:

“The score is also very important,” says Gunn. “I worked very hard early on with Tyler Bates, our composer, whom I’ve done three other movies with, to write part of the score ahead of time so that I’m able to use it on set for big emotional sequences and big action sequences. We can actually play the music on set and the actors can really understand where we’re going with it tonally. Our actors have a much better idea of what this film is because of the music that we use, both score and soundtrack.”

Cool stuff all around.  I'd have expected nothing less from Gunn after the film's trailer showed off just how well music is incorporated into the movie and its marketing.  Just another notch in the belt of what I hope is Marvel's biggest surprise yet.