Like the other band formerly known as The Warlocks, The Velvet Underground spent their entire career in a state of constant change punctuated by extended jams. Unlike the Grateful Dead, The Velvet Underground never quite sustained a workable audience during their half-decade on the road. And though they did attract a nascent audience taping scene, there are (most likely) no Velvet Underground tapes left to be discovered that sound a fraction as good as the soundboards recorded at the Matrix in San Francisco over two nights in November 1969. Released in fragments over the years, the unexpurgated four sets need to (at least) be absorbed by any rock-and-roll fan— one of the very few clear documents of the live Velvet Underground in the wild, and (at most) used to indoctrinate those who don’t understand the fuss. Probably semi-unrecognizable to anyone expecting the Warholian art-stars of a few years earlier, the four-and-a-half hours of music fire from top-notch, tightly wound proto-punk (two equally excellent skronky versions of “I Can’t Stand It”) to early glimpses of Lou Reed’s transgressive ‘70s camp (“After Hours,” “Over You” and chunks of delightful banter). The songs are in progress (two versions of “Sweet Jane” both have different alternate verses) and the music is alive and at the whims of its creators. The final documentation of the quartet with both Reed and drummer Moe Tucker together, The Complete Matrix Tapes is a goodbye to a lot more than the ‘60s. “This one’s really dynamite,” Reed says before “Rock and Roll” and he ain’t lyin’.