The following is an excerpt from the research article on "Swami Vivekananda's Voice Recording" that appeared in Vedanta Kesari Magazine:

Research Article: https://issuu.com/srkmath/docs/the_vedanta_kesari_august_2010/s/11872762

The much-asked question whether there are any voice recordings of any of the speeches of Swami Vivekananda at the Chicago Parliament of Religions in 1893 has been investigated by MS Nanjudiah. Swami Chidananda of the Vivekananda Vedanta Society, Chicago, indicated to Nanjudiah that he had made enquiries and found that there were no such recordings. Swami Chetanananda of the Vedanta Society of St. Louis also followed up this matter and corresponded with the Chicago Historical Society (Archives and Manuscripts) and the Library of Congress, as suggested by the Historical Society. The conclusion was that there were no such recordings.