Here is a recording of a performance of 45' for a Speaker performed by James Sanders (the track is 42 mb). The musical pieces are 26"1.1499" for a String Player performed by Daryl Giuliano and 27'10.554 for a Percussionist performed by Caleb Herron. This performance took place on September 6, 2012 at the Goat Farm, Atlanta, as part of The Ten Thousand Things, a celebration of the life and work of John Cage on the 100th anniversary of his birth, presented by the Atlanta Poets Group, Bent Frequency and the Chamber Cartel.
All three pieces are from the collection of works known as the Ten Thousand Things. You can read more about 45' for a Speaker at Richard H. Brown's blog, A Year from Monday, and more about the Ten Thousand Things from James Pritchett.
Here is a recording of 45' for a Speaker by itself (also performed by James Sanders).
Wesleyan University Press