The primary impetus behind this ambitious 12-disc box set is to gather all nine of the Grateful Dead's Warner Brothers titles. However, the staggeringly high quotient of previously unissued bonus material rivals - and at times exceeds - the content of those original albums. The Golden Road (1965-1973) truly has something - and usually a lot of it - for every degree of Deadhead. Working chronologically, the bonus material begins before the beginning so to speak, with the two-disc sub-compilation aptly titled "Birth of the Dead," a project actually green-lighted by Jerry Garcia in the mid-'80s. Disc one features studio recordings by a primordial incarnation of the band known as the Warlocks and later the Emergency Crew. Disc two contrasts their studio efforts with some of the earliest surviving live Grateful Dead recordings from July of 1966…