One word is used throughout Dave Grohl's documentary "Sound City:" human. It's used more than any of the musical equipment scattered throughout the studio – though don't worry; the rockers do get around to rocking. It serves as a potent reminder that music is not just a business or entertainment. Communicating emotion through music is a uniquely human activity, and even though computers and auto-tune are now at our fingertips, the most important tools a musician can have are heart, passion and a desire to rock.

Movies are much the same. Producers and directors now have computer effects that can make all sorts of newfangled creations, but it's passion and heart that can help make a movie come alive. Such is the case with "Sound City," a heartfelt, exuberant tribute to the old days of recording that oozes with affection from everyone involved.

And if that's not enough, it comes with a kicking soundtrack. Times have been far worse.

Grohl's rock doc focuses on Sound City, a famous recording studio tucked away in Los Angeles. The dumpy little studio didn't look like much, but it served as the home for legendary artists like Neil Young, Fleetwood Mac, Tom Petty, Rick Springfield, Foreigner and Nirvana.

It wasn't the kitschy doormat or carpeted walls that brought these incredible acts into Sound City's office. Instead, it was a combination of the main recording room – not designed for music, but by a twist of fate acoustically perfect for drums – the unique Neve mixing console that could fine-tune almost every element of a song and the cozy atmosphere, provided by workers like Paula Salvatore and Tom Skeeter. The gold and platinum records on the walls certainly helped as well.

For most of the film's first hour, "Sound City" lingers on the stars and albums that made the studio so beloved, but things can't stay the same forever. Eventually, the computer and digital recording software like Pro Tools came along, changing the way artists would record forever. No longer were tape, practiced performance and experienced technicians needed. Wannabe rock stars could just pop their music into a computer and let the technology turn it into a hit. Skill and soul? Optional.

To add to Sound City's woes, the modest facilities could no longer keep up with the fancy, elaborate studios popping up around Los Angeles. Eventually, the studio would have to make like some of its rock star clients and fade away, closing in 2011.

"Sound City" is clearly a passion project for Grohl (who also serves as a producer). The Foo Fighters' frontman witnessed Sound City firsthand when he recorded "Nevermind" as a member of Nirvana in the '90s, and after the studio closed, he bought its famous mixing console and installed it into his own home studio.

The love shows on screen as well. Simple scenes, like a Sound City technician briefly showing how he edits and cuts the recorded tape, are filmed with a warm sense of nostalgia and deep respect. The film also gathers a staggering amount of musicians and former employees to give entertaining and surprisingly honest interviews – namely Rick Springfield, who talks solemnly about his rough departure from the studio.

It's fascinating hearing these legends talk about their craft – whether they're recalling memories, discussing the technical details that make music great or just geeking out about an album or band that they love. No matter the topic, they all have fun anecdotes to share, adding color that makes Sound City feel like a fully realized place. This isn't just a self-indulgent nostalgia trip for rock stars yearning for the old days; the audience feels like they're emotionally along for the ride too.

In his enthusiasm to tell as much of Sound City's story as possible, the doc's focus gets a little scattered, hopping from the studio's origins to Fleetwood Mac to Tom Petty, then back to the studio again. Despite tackling so much, Grohl never sells any of the little vignettes or stories short, and each one adds to recreating the warm, lived-in musical community that was Sound City.

The final act takes a surprising detour, following Grohl and the making of a tribute album to the studio with some of Sound City's most famous artists (and Paul McCartney, who didn't record at Sound City, but who's going to say no to playing with Paul McCartney). The interviews begin to get repetitious, hitting the same note – music is better with people. It plays a bit like "Sound City" is circling the runway, but thankfully, it's a holding pattern with a killer soundtrack of original collaborations.

Put simply, "Sound City" rocks, but that's to be expected from a rock doc. It's all of the feelings and memories packed into its 108 minute running time that make Grohl's film something even better: human.

"Sound City" will play for one-night only at the Oriental Theatre tomorrow night at 7:00 p.m.