For Jenee DeAngelis, working on “Cold Case” compares to taking a graduate course in Music 101.

As the hit procedural drama’s music supervisor, DeAngelis is called upon each week to tackle a different era of tunes. Some are easy to populate, such as an episode about an unsolved murder from 10 years ago. Others require a little digging: most notably, the seg about a woman who was killed in 1919.

“This has definitely been the best school,” says DeAngelis, whose “Cold Case” stint is her first as a music supervisor. “I’ve learned so much more about music.”

Unlike most procedural dramas, songs are an incredibly important part of “Cold Case.” The CBS series focuses on dead-end cases that are reopened; re-enactments of the victim’s final days are shot to evoke the time period as realistically as possible.

That means production design, hair and makeup must truly reflect the year — as should the music.

“That was part of the beauty of (creator Meredith Stiehm’s) original pitch and the conception of the show,” says showrunner Veena Sud. “We go back into the life of the victim, so that they’re not just a statistic but a real human being.

“The songs are such an important and evocative part of the flashbacks. The feedback we get when we put a song into a scene, it brings the viewer back to his or her high school days. It’s a very visceral way to evoke memories.”

It has also become a good way for “Cold Case” to attract attention and stand out from the crowded pack of crime dramas.

Most episodes contain a wide variety of songs from the year in question — about six per seg. The producers strive to avoid showcasing any songs that were released after the flashback year in question.

Additionally, several episodes have centered on a single artist. Most recently, one seg about a 1994 murder exclusively featured the music of Nirvana and the late Kurt Cobain. Others devoted themselves to tracks from the likes of Bruce Springsteen, U2, Bob Dylan, John Mellencamp and Johnny Cash.

Now that “Cold Case” is in its seventh season, DeAngelis says it’s easier to get artists onboard.

“I definitely think it’s because we’ve forged such a good reputation with how we use music, and the fact that people enjoy the series,” she says.

Best-laid plans

The road to getting a song or artist on the air varies. Much of the time, it starts with a writer who chooses an era to tackle.

“It’s up to the individual writers, as they’re thinking about songs from their childhood or the era of the characters,” Sud says.

Then DeAngelis starts drafting a sheet of appropriate songs.

“We start getting script outlines ahead of time,” DeAngelis says. “At this point we start gathering music, and a lot of times writers will ask me for pitches. I’ll come up with a bunch of songs from that time, although the further back you go, the harder it is.”

Next, the showrunners will choose which songs to keep, and DeAngelis sends out requests. The newer the song, the easier it is to identify who owns publishing rights. The passage of time made the 1919 episode particularly difficult, DeAngelis notes.

As for the special, single-artist episodes, inspiration comes from a variety of places. Sometimes it’s the writers who come up with the idea: Stiehm, for example, took several Springsteen songs and then tailored scenes to fit each tune. Ditto the Dylan seg.

“From the beginning, I was very excited about the Dylan episode, as the themes in the show were similar to the journey the artist went through,” Sud says.

In other instances, record labels and song publishers will now pitch “Cold Case” scribes certain artists and tracks.

“I cannot believe the people we’ve gotten to do this,” DeAngelis says.

Not every song ultimately works out. The producers frequently are jazzed about including a song, only to find (while watching a rough cut) that it doesn’t jibe with the scene.

“You’ll imagine a scene or how a song goes, but then when you see the actual cut, a lot of times it plays out differently,” Sud says.

The show’s music-intensive production also has a downside: “Cold Case” hasn’t yet been released on DVD due to clearance issues; off-net syndication will also be a problem.

Those rights won’t come cheap, but Sud says she can’t imagine ever seeing an alternate version of “Cold Case” stripped of its music.

“It would feel like a very different show if we didn’t have those songs,” she says.