It's funny how electronic music is frequently regarded as the next big thing even though electronic music has been around almost as long as electricity itself. If anything, rock is the interloper. It's only in the last 30 years or so that musicians have managed to make machine music more accessible; before that, electronic composers existed in the nether regions between artist and scientist, experimenting with new sounds on the cutting edge of now-primitive but then-progressive technology. OHM: The Early Gurus Of Electronic Music is an impressively packaged three-disc set that collects seminal works (or snippets thereof) by dozens of revolutionary or radical musical figures whose names are dropped more often than their music is heard. Beginning with a Tchaikovsky piece performed by theremin prodigy Clara Rockmore and continuing through such prominent names as John Cage, Edgard Varese, Karlheinz Stockhausen, Milton Babbitt, Steve Reich, Morton Subotnick, David Tudor, Terry Riley, Iannis Xenakis, La Monte Young, Bernard Parmegiani, Alvin Lucier, and Brian Eno, OHM does a surprisingly effective job encapsulating musicians defined by their disdain for categorization. Granted, certain pieces are more accessible than others—and some are pretty silly—but all represent an obsession with sound for sound's sake. It's perverse how even the most minimal pieces were often composed on mammoth devices: With synthesizers smaller than ever, it's hard to imagine music machines that took up entire rooms, let alone the geniuses who built those boxes of wires and switches. One such genius was Raymond Scott, one of many included in the OHM set. An inspired and eccentric jazz composer (several of his manic songs were adapted by Carl Stalling as scores for classic Warner Brothers cartoons), Scott was also an early synth experimenter and inventor. While most of his creations were novelties, his music was eerily prescient: The three-album set Soothing Sounds For Baby, intended as proto-chill-out music for toddlers, resembles Aphex Twin despite coming out several years before Richard D. James was born. The new Manhattan Research Inc. compiles two discs' worth of Scott's previously unreleased work for radio and television, primarily ads (some of which were joint efforts with a young Jim Henson). Scott's early stabs at sequencing and emulation sound strange even today, and the set's 140-page booklet confirms that the inventions—machines such as the Clavivox, the Karloff, and the Electronium—were even stranger. OHM's rich bounty of boundary-breakers and the treasure trove of Scott-illuminating material just goes to show that the world's stock of sonic curiosities is both endless and endlessly fascinating.