That's what violinist Karen Shinozaki has been doing for more than a decade. Here's a partial list of her concurrent employment: Santa Rosa, Berkeley, and Marin Symphonies, New Century Chamber Orchestra, Symphony of the Redwoods, San Francisco Chamber Orchestra, Santa Rosa Chamber Players, Berkeley Contemporary Chamber Players, Sor, Worn and Adorno Ensembles; she also performs as a regular extra with the San Francisco Opera and Ballet Orchestras.

When you attend concerts in the larger Bay Area, from Santa Rosa to Sacramento to Monterey, you will soon notice the same musicians popping up everywhere. Who are these wand'ring minstrels? They are the heroes of a new film, by Tal Skloot and Steven Baigel, "Freeway Philharmonic." It will be shown on PBS stations at the end of the month, including San Francisco's KQED, ch. 9, first at 6 p.m., Sunday, Jan. 27. Theater screenings are scheduled at the Rafael Film Center, at 7 p.m., Jan. 24, and in the Cerrito Speakeasy Theater, at 7 p.m., Jan. 29.

All around the country, for every large, full-time orchestra - such as the San Francisco Symphony - there are dozens of small orchestras, using freelance musicians. "Pickup orchestras" thrive in the larger Bay Area, with many commuting musicians, playing in as many as eight orchestras, these "road warriors of classical music" driving hundreds of miles on the freeways and rural roads. In fact, bassoonist Karla Ekholm has 330,000 miles on her old car. Trombonist Bruce Chrisp gets vegetable oil discarded by a Chinese restaurant to power his Mercedes.

They, and the documentary's other main characters - French hornist Meredith Brown, cellists Robin Bonnel and Eugene Sor, trumpeter Kale Cumings - both hope for and dread "triple weekends." Bonnel explains: "10 in the morning, rehearsal in San Rafael, with the Marin Symphony; 2 o'clock, dress rehearsal in Santa Rosa, 8 o'clock, the concert. You get home at 11:30, then a rehearsal at 10 the next morning, then you're out here, playing a concert at 3, another at 7:30. The next morning, there would be a rehearsal with the New Century Chamber Orchestra in the morning and afternoon, a concert at night..."

All that through traffic jams, rush-hour traffic, freeway accidents and near-misses. And yet - while envying the stability and security of colleagues playing with big orchestras, and auditioning from time to time - musicians of the Freeway Philharmonic put their love of music into their busy lives and manage to enjoy much of it with great gusto.

Full-time orchestras, they agree, develop their sound as musicians are sitting next to somebody for 10 years, and can anticipate every movement, every nuance. Freelancers rarely sit together in the same section, play together maybe once a month, but it can also make for more spirited, more exciting performances. Also, they get to play opera, chamber music, symphonies - the kind of variety you don't get playing with just one orchestra. The downside is mostly logistical, color-coding orchestra schedules to make avoid overlaps and conflicts, driving hundreds of miles to rehearsals and performances... and then driving back home. Few would do this without an overwhelming passion for what they do. If they didn't, hundreds of regional orchestras - unable to maintain a regular staff - wouldn't exist.

"Music is my spirituality, my personality, my ecstasy…when it's good, there's nothing better and if you can do this for a living, good gig," says Bonell, and he drives on.

Janos Gereben