Call it bluegrass, call it newgrass, whatever, that uniquely American form of music was given a lively showcase at the Lobero Theatre on Tuesday night by three masters of the form.

Jerry Douglas played dobro, Sam Bush covered mandolin and fiddle, and Edgar Meyer grounded the trio on double bass. The three have again joined forces to tour, after pursuing their individual professional paths. Dressed down, these are men who bring no pretense to their appearance, in clothing best described as “what to wear while hanging out.” The music is what it’s all about.

Douglas has been called “dobro’s matchless contemporary master” by The New York Times, regularly tours with Alison Krauss and Union Station, and records with artists the likes of Béla Fleck, Paul Simon and Elvis Costello, among many, many others. Douglas was also the recipient of a National Heritage Fellowship from the National Endowment for the Arts in 2004, not to mention 12 Grammy Awards during his career.

Bush is a virtuoso on mandolin and fiddle, a perennial star on the Bluegrass and Newgrass tours, and the winner of numerous honors, including the International Bluegrass Music Association’s Mandolin Player of the Year for 2007. He has recorded and appeared in person with country stars Dolly Parton, Doc Watson and Emmylou Harris, among others.

The third member of this all-star trio was Meyer, whose double-bassist mastery apparently knows few, if any, limits. He performs classical, bluegrass and jazz, and his collaborators have included Fleck, Joshua Bell, Yo-Yo Ma, James Taylor, Mary Chapin Carpenter and the trio Nickel Creek.

In keeping with their unassuming appearance, the three did not provide a printed program but played a succession of pieces that were by turn lively, low-down and rapid-fire.

Douglas led the way on dobro, starting with a piece the group calls “Unfolding.” The dobro is a guitar with a metal resonator instead of a sound hole. In the hands of Douglas, it is a kind of magical mystery tour of heightened guitar technique and melody.

The first half of the program rambled through pieces with names like “Junior Heywood” (“we picked the name out of the phone book”), “Mountains” and something Meyer insisted on calling “The Emphysema Two-Step.” The group’s humor, collectively and individually, is definitely down-home.

The second half was highlighted by a plaintive and lovely “Early Morning,” evoking some idyllic dawn in the Appalachians. Also included was a foot-stomping, high-speed concoction that the trio calls “Death By Triple Fiddle.”

Nothing if not gentlemanly, the players also said nice things about the Lobero and about how “purty” Santa Barbara is. The music sure was “purty,” too.

— Margo Kline covers the arts as a Noozhawk contributor.