If there is a theme to this box set culled from the sessions that comprise Frank Zappa’s first solo album- 1969’s Hot Rats– it would be an exploration devoted to the creative process.  This six-disc set does ask, implicitly, for a level of patience and focused interest amidst the repetitive nature of capturing “the one,” examining how the compositional virtuoso that is Zappa walks and works his way deliberately through the construction of each song that would become his mostly instrumental debut masterpiece.  Zappa is listening for something and only he knows when he hears it, and it’s fascinating to follow the sequence as he builds such classics as “Peaches En Regalia” and “Little Umbrellas.”  His directions from the booth are urges more of feel and emotion rather than technical notes; Ian Underwood on piano serving as the first mate on Zappa’s compilation of jazz-inflected journeys.  So much of Hot Rats ultimately would be a showcase for the incredible improvised soloing of Zappa on guitar or guests Jean Luc Ponty and Don Harris on violins, but it’s the assembly of the foundation for each track- namely the domain of the rhythm section- that gets the attention here.  The payoff is the proper album, in sequence and from the 1987 digital re-mix Zappa produced, himself, included as part of the fifth disc.  By the time it arrives, it’s as if the ear has been trained to tune in to what Zappa was looking for all along, and by virtue, hear how this remarkable album was meant to be heard.  The set is also loaded with nuggets from the Vault including never-before-seen photos, rare and unreleased tracks and mixes, an essay from The Simpsons creator Matt Groening, and even a “Zappa Land” board game.  In short, just another fun, entertaining, and educational essential from the genius musical mind of Frank Zappa.