"Mademoiselle" is the first single released from Styx's Crystal Ball album. Its B-side was "Light Up", from the previous album, Equinox. It peaked at #34 on the Billboard Pop Singles Chart, Styx's third top 40 hit. It also reached number 25 on the Canadian RPM singles chart on the week of January 22 1977. Most of the early pressings on the U.S. 7" single played too fast (they were cut at the wrong speed). This made the song sound high-pitched. Instead of 45 RPM, the A-side seemed to be suited at 39 RPM. The B-side "Light Up" was cut correctly, however.

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