Musical-Boxes -- The only element not absolutely assured, in the result of experiments thus far made--which stands in the way of a perfect reproduction at will of Adelina Patti's voice in all its purity--is the single one of quality, and even that is not totally lacking, and will doubtless be wholly attained. If, however, it should not, the musical-box, or cabinet, of the present, will be superseded by that which will give the voice and the words of the human songstress.
This 'probability' of 'Musical-Boxes' is an extension of Edison's other 1878 music related prediction which he labeled "Music." "Music was exemplified by his phonograph being able to reproduce the song of a friend who in a morning-call may "sing us a song which shall delight an evening company." The challenge for Edison's 'musical-box' probability, however, was a higher standard. Sound quality needed to equal a songstress and his example was the desire to reproduce the celebrated "Adlina Patti's voice in all its purity." According to Edison in 1878 his phonograph was not yet there in quality of sound...but "doubtless," he wrote, it will "be wholly attained."
Munsey's Magazine, 1906
Puck - Adlina Patti promoting "Pears' Soap" December 1889
Chocolat Suchard Tradecard
Victor Supremacy meant that voices of "finest, purest gold" could be perpetuated for all time if they were captured on a Victor Record. Life 1918
"the real thing -- you can't tell it from the actual human voice!" 1909
"Home is more comfortable than an opera house, and a better place to enjoy the magnificent voices of the greatests opera stars," 1910