The guys from the Zzymzzy Quartet have simple ambitions: they just want to play it like it was when it was unamplified, melodic, swinging, dreamy, full of sly surprise. From the Prohibition through the Second Big War, the glory days of Louis Armstrong and Duke Ellington are being recaptured humbly and with humor in San Diego by four musicians who know it don’t mean a thing without that swing: