Jazz music, always known for its spirit of improvisation, was hardly the medium for composers or producers during its first 50 years. Even the greatest early arrangers — Duke Ellington, Fletcher Henderson, Don Redman — allowed plenty of room for solos, and would've been deserted by most of their musicians if they hadn't. All of which explains why Raymond Scott was never considered a jazz artist. His pieces, impressionistic yet rigidly composed, did use all the same components of a jazz band and exhibited close superficial similarities to Duke Ellington's early jungle band and the Benny Goodman Orchestra. The difference lay with his insistence on perfection, in his recording techniques and the members of his band. The Raymond Scott Quintette was a clean, technical, utterly precise swing machine — the logical progression, in his mind, of the noisy jazz racket originally delivered on record by the Original Dixieland Jazz Band in 1917. Microphone Music, another Scott-related reissue by the Basta label, is a two-disc bonanza of unreleased titles, rarities, and rehearsals from the late '30s that will taste of manna from heaven for listeners who spent a decade in the wilderness after Columbia's greatest-hits volume, 1992's The Music of Raymond Scott: Reckless Nights & Turkish Twilights. These certainly don't sound like afterthoughts, either; Scott took quality control very seriously, and the result is a set of 40 splendid, fascinating songs that often sounds better even than the Columbia release. Most of the songs are new to CD, and even the familiar titles (like the Scott perennial "Dinner Music for a Pack of Hungry Cannibals") are presented in radically different interpretations. Drummer and percussionist Johnny Williams (father of composer John Williams) is revealed as an extraordinary talent, not just keeping time for the quintette, but splitting it into halves and quarters with his brisk, perfectly timed fills. As for Scott, who's usually recognized solely as a compositional or arranging genius, the focus here is on his talent for sound reproduction. The title is a nod to the importance of engineering and microphone placement in his music — a reprint of a Popular Mechanics article appears in the liner notes — and his constant recording experiments produced dynamic music utterly unlike anything heard before, since sound had never been picked up and amplified the way Scott did it. The relative scarcity of Quintette recordings is enough to boost this set into recommended status, but the bounty of fabulous music inside makes it essential for fans and highly recommended for the uninformed.