Their early material was hard edged blues-rock influenced by Bo Diddley and Jimmy Reed, much like that of their contemporaries like the Stones and The Yardbirds. They were known for wild "rock and roll" behavior and shocking the establishment ; their song "Midnight to Six Man" defined the Mod lifestyle. Beginning in 1966 they drifted more towards psychedelia, originating the concept album with 1968's S.F.Sorrow. From this point on they would enjoy less in the way of commercial success but the devotion of a strong cult following especially on critics and other rock musicians as well. Their material in the early 1970s tended towards more the hard rock and early heavy metal end of the spectrum, on albums like Silk Torpedo, although still blues based. 1980's "Cross Talk" saw them incorporating influences of punk and new wave into their hard rock sound ; it was an artistic but not a commercial success like most of their records.