They were once a quartet. Then they were a trio. From time to time they’ve been a duo. But when Tokyo Tramps return to the Jasper Hill Café on Nov. 25 for an evening of blues-rock originals and covers, they’ll stick with the trio format: married founding members Satoru Nakagawa (guitar and vocals) and Yukiko Fujii (bass and vocals) along with drummer Jungho Kang.Nakagawa and Fujii, both natives of Japan, met while they were students at Berklee College of Music, but [...]