Recognize this instrument ? Well, hardly, for it's the new Theremin Ether-wave Music box. And of course you have not failed to note the lovely young lady -- she is MME ALEXANDRA STEPANOFF, musician of marked ability, all of which is required to coax exquisite melody from this remarkable instrument.

Albert Glinsky (2000) Theremin: Ether Music and Espionage, University of Illinois Press, стр. 86 ISBN: 978-0-252-02582-2.

"​In July, writers for two New York Communist organs, A. B. Magil, of the Daily Worker, and William Abrams, of the Daily Freiheit, dropped in on the inventor for a feature story. “Prof. Leon Theremin led the way into the modestly furnished bedroom of his suite at the Plaza Hotel,” Magil wrote. “... a pupil of his was practing on the new ether-music instrument.” The pupil was Alexandra Stepanoff, Theremin's first student on U.S. soil -- a young, recent immigrant to America. Slender and graceful, with delicate features, dark, smartly cropped hair, and an assured smile, she remainiscent of the very young Galbo. In Russia she had been a concert singer and now, under the professor's spell, she fluently transferred her vocal technique to the ether instrument. Alexandra had come to the inventor's attention through the network of New York's Russian community with which he had surrounded himself, and along with Goldberg she became one of the first discilples of the instrument. "