There are few summer music events more charming than Southwest Chamber Music’s outdoor series at the Huntington Library, Art Collections and Botanical Gardens. On the splendid terrace overlooking magnificent garden vistas and ancient statues, consummate musicians perform works classical and contemporary as the sun sets, the birds join in with their own evensong, and the occasional misplaced sprinkler sprays the audience. It’s all as romantic as can be, and the series opens this weekend with magical guest harpsichordist Patricia Mabee soloing in Bach’s Brandenburg Concerto No. 5 and de Falla’s Concerto for Harpsichord and Five Instruments; program also includes Mozart’s Quartet for Flute and Strings, K. 298, and String Quartet, K. 155. Huntington Library, Art Collections and Botanical Gardens, Garden Terrace, 1151 Oxford Road, San Marino; Fri.-Sat., July 7-8, prelude talk 7 p.m., concert 7:30 p.m.; $38 terrace, $28 lawn seating. (800) 726-7147, www.swmusic.org.