Ives created a series of sketches for the Universe Symphony in 1915, around the time of his Fourth Symphony, but never completed it. His sketches and writings suggest a massively complex microtonal work.

"The 'Universe in Tones' or a Universe Symphony," he wrote, is a "a striving to present & to contemplate in tones... the creation, the mysterious beginnings of all things, known through god to man, to trace with tonal imprints the vastness, the evolution of all life, in nature of humanity, from the great roots of life to the spiritual eternities from the great unknown to the great unknown. "

Composer Larry Austin released his own version, based on the sketches and assembled over two decades, in 1994, and it has been recorded by the RundfunkSinfonieorchester Saarbrucken and the Cincinnati Philharmonia Orchestra.

Austin's edition, however, included newly composed sections. Reinhard, the director of the American American Festival of Microtonal Music, set out in the 1990s to complete the work "exclusively" from the sketches. His version was premiered at Lincoln Center's Alice Tully Hall, under the auspices of the AFMM, in 1996; the recording, created in a series of audio "layers" rather than in a live performance, took four years to complete.

Reinhard and Thorne will discuss the new CD on New York's WNYC 93.9 FM on June 6 at 2 p.m.