“Right now we’re performing at about seventy percent capacity,” declared The Roots emcee, Tariq "Black Thought" Trotter about forty minutes into their show last Sunday night at Santa Clara University.

“With your help, we gonna start bringing that up, so, by the time we finish, you will have no doubt that we are the legendary Roots crew,” he continued.

The band made good on their promise, concluding their show after about two hours and then going on to play a forty minute encore in which they covered such varied artists as Burning Spear, Salt and Pepper, Black Sabbath, N.O.R.E, The White Stripes, Talib Kweli, Nirvana, The Eagles and Sir Mix Alot.

The Roots are widely recognized as one of the finest live groups in the world of hip hop. Their first album, “Organix,” was produced simply so that they could have something to sell at their shows. In a recent article in “Paste” magazine, they were compared to the Grateful Dead of rap. The crew spends roughly 250 nights a year on the road, having a combined ninety years of touring experience among all its members.

The crowd at the Leavey Center pulsed with a nervous expectant energy as they waited for The Roots to take the stage. The opening act, Forty Watt High, played a great set, but they stirred up the largest cheers when they kept reminding the audience that The Roots were waiting backstage. The stage set itself gave away that this wasn’t just any rap group — there were two drum sets, a bass and lead guitar, a keyboard and three mics across the center of the stage draped in white athletic towels.

The stage managers ran about strategically placing bottles of water and Pepsi’s and Red Bull’s for the musicians. Then the lights went out and the crackly spoken word intro to The Roots new hit, “Star,” came through the speakers as they marched up the stairs at the back of stage to the sound of thousands of screaming fans.

Black Thought took the mic as the rest of the group got comfortable at their instruments and started in on a three minute solo rap of “Web,” a song that does without a chorus, just four minutes of non-stop rhyming and bliss.

As he finished off, the rest of the group joined in and they dove back into “Star.” The Roots are one of the few groups in hip hop that feel totally at ease with improvisation and simple jamming. Only in the strictest of venues, such as at this week’s NAACP awards, do they play a straightforward version of their songs. Halfway through “Star,” Black Thought cut in, “We never know how this shit is gonna end.”

Most of the set came from their most recent album, “The Tipping Point,” which is currently up for a pair of Grammys. There were a fair share of flashbacks to the days of “Illadelph Halflife” and “Things Fall Apart,” with less of an emphasis on their big commercial splash, “Phrenology.” “Phrenology” is a point of debate for many serious fans. Historically, The Roots have had more critical than popular success, and their ability to constantly border on the mainstream without altogether submitting to it may be part of their huge appeal. While “Phrenology” brought The Roots the widespread success that had eluded them up to that point, some thought of it as the band selling out on their values.

The Roots are a dynamic group, quite open to adapting to new members and slight changes in sound. The core group is made up of Black Thought, drummer ?uestlove, bassist Leonard “Hub” Hubbard and keyboardist Kamal Gray. The Roots were also the launch-pad off which now famous beatboxer Rahzel was first sent into orbit. On The Tipping Point, the beatboxing is absent, but in its stead are the guitar of new Root’s member Captain Kirk Douglas and the percussion of Frank Knucles.

More than anything, it was clear that The Roots were having fun while they were performing on stage. They were constantly challenging each other to push their limits, but it came across as nothing but playful banter. In the middle of one of Black Thought’s raps, Kamal slowed the beat on the keyboard down, at which

point Black Thought immediately began stretching his words and drawling, rapping in mock slow motion. . ?uestlove and Frank Knuckles had plenty of fun dueling from their respective percussion sets, always building up to one coordinated rhythmic sound. While the crowd stands there swaying and shaking their heads in awe, The Roots shuffle around on stage joking with each other and laughing, ?uestlove’s wide smile remains always visible under his enormous afro as he presides over his hip hop circus.