Find your groove in Billy Cobham’s rhythmic spectrum with our Song of the Day. The great fusion drummer’s debut leader album Spectrum was released this month in 1973. “Quadrant 4,” with its rapid-fire drumming, searing guitar solo, laser-like synths and bluesy main riff, has become a ’70s jazz classic and the perfect example of what happens when speed-metal and jazz combine. Prepare to have your face melted.