In what has been described as either an extension of bebop ora backlash against cool, a style of music known as hard bop developed in the 1950's. This style also downplayed the technically demanding melodies of bebop, but did so without compromising intensity. It did this by maintaining the rhythmic drive of bebop while including a healthier dose of the blues and gospel music. Art Blakey And The Jazz Messengers were, for decades, the most well-known exponent of this style. Many musicians came up through the so-called "University Of Blakey". Blakey's early groups included pianist Horace Silver, trumpet player Clifford Brown, and saxophonist Lou Donaldson. Clifford Brown also co-led a group with Max Roach that is considered one of the great working quintets in history. Several albums from these groups are available today and all are recommended. Miles Davis also recorded several albums in this style during the early 1950's. There were also a number of groups led by or including organists that came from this school, with even more of a blues and gospel influence. Organist Jimmy Smith and tenor saxophonist Stanley Turrentine were popular players in this genre.