×∞Multiplies(増殖,Zōshoku?, lit. "multiplication") was a mini-album by Yellow Magic Orchestra released in 1980. It contains a mixture of songs and instrumentals by YMO (including a humorous reworking of Archie Bell & the Drells' "Tighten Up"), interspersed with comedy sketches. These sketches are performed by Snakeman Show in both Japanese and English, with YMO participating in some of them.
×∞Multiplies was released in several formats worldwide. The original Japanese pressing came on 10" vinyl. The United States pressing compiled tracks from both this record and from Solid State Survivor, which had not been released there, while dropping the comedy sketches. The United Kingdom released ×∞Multiplies with additional tracks culled from Yellow Magic Orchestra. All re-issues from 2003 onward reverted to the original Japanese tracklisting (the version with the American tracklisting had been re-isseud various times over the years until 1999, when both Japanese and American issues were remastered under Haruomi Hosono's supervision and each received a new set of liner notes, the Japanese's by Fantastic Plastic Machine and the American's by Derrick May).
The tracks differ slightly between the Japanese and US versions: In the original release Nice Age has an abrupt ending and other tracks are crossfaded between the Snakeman Show sketches; in the US version these have clean intros and endings and Jingle 'YMO' is listed as part of the Nice Age track.
Upon release, the US version was well received by the Stereo Review, which described the recording as "Terrific" and the performance as "Techno-pop fun." The magazine stated that the "time is right" for the band's "highly technological blend of dance rhythms, heavy metal, and pop melodies" while noting that "Rydeen" in particular "sprints by at a fast clip, ticking off a sprightly tune against a continuous bass-and-drum texture," though the "more rock-style efforts" were not as well received, with the magazine stating that "YMO's electronic tricks" and "the rock sensibility just don't seem to mix."Allmusic later reviewed the Japanese version, describing the record as a "bizarre album" and scoring it 2.5 out of 5 stars.