"Repetition," declared Brian Eno, "is a form of change." Although the famed conceptualist was referring to the static processes in his pioneering ambient music, I think of Eno's dictum whenever I go to hear a community orchestra.

Like professional (i.e., salaried) bands such as the Seattle Symphony, community orchestras play the warhorses we know and love—symphonies by Beethoven and Tchaikovsky, Mozart concertos, etc.—but with a wider range of results. Some local groups, especially Orchestra Seattle, Seattle Philharmonic Orchestra, and Philharmonia Northwest can, on a good night, rival just about any orchestra anywhere. Others, like the Lake Union Civic Orchestra (LUCO) and the Puget Sound Symphony Orchestra (PSSO), usually sound scrappier, sometimes trading in precision for a palpably exhilarating (or frustrating) feeling of risk. At one LUCO concert a couple years ago, I wasn't surprised when a few bum notes in the Poco Allegretto of Brahms's Symphony No. 3 were quickly redeemed by a world-class horn solo. If you want to hear classical music's big hits sound fresh, dangerous, and possibly transcendent, go hear a community orchestra.

Community orchestras take bigger risks on new music, too, giving local (and otherwise unknown) composers a chance. Nestled in an upcoming PSSO performance (Sat May 16, Town Hall, 7:30 pm, $7 adv/$10 DOS, see www.psso.org for details) of The Planets by Holst and Debussy's Nocturnes is an overture by the band's own Kevin Tao, cheerily described on the PSSO site as an "instrumentalist, composer, and poker shark."

Other community orchestras include the summertime Northwest Mahler Festival Orchestra (check www.nwmahlerfestival.org for their July 19 concert) as well as two outfits with concerts on June 7, the Musicians Emeritus Symphony Orchestra (www.mesoseattle.org) and the Pontiac Bay Symphony Orchestra (www.pontiacbay.org), which survey film scores (their June 7 concert includes music from Aliens, Psycho, and The Abyss). Just outside of Seattle you can catch the Cascade Symphony (www.cascadesymphony.org) or hear the Rainier Symphony scale the summit of Mahler's mammoth Symphony No. 2 this weekend (see www.rainiersymphony.org for details). Remarkably, the Burien-based Northwest Symphony Orchestra (www.northwestsymphonyorchestra.org) program music by local composers on just about every concert, from the Degenerate Art Ensemble's Joshua Kohl to the Seattle Symphony's composer-in-residence Samuel Jones.

Finally, fans of the avant face a tough choice Friday night: Chicago composer Olivia Block (Fri May 15, Chapel Performance Space, 8 pm, $5–$15 sliding-scale donation) makes her first Seattle appearance. That same night, percussionist Bonnie Whiting Smith (Fri May 15, Gallery 1412, 8 pm, $5–$15 sliding-scale donation) performs compositions by Richard Johnson along with pieces by John Cage, Daniel Alejandro Almada, Nicole DeLaittre, and "a quirky little arrangement using Radiohead's music and a traditional folk song." recommended