Signals is the ninth studio album by the Canadian rock band Rush, released in 1982 Signals was the follow-up to the successful Moving Pictures. Stylistically, the album was a continuation of Rush's foray into the technology-oriented 1980s through increased use of electronic instrumentation such as keyboards, sequencers, and electric violin. Another noticeable change was in terms of song length and lyrical compression. The album reached #10 on the Billboard album charts and was certified Platinum (1,000,000 copies sold) by the R.I.A.A. in November 1982.

Systematic Chaos is the ninth studio album by American progressive metal band Dream Theater. Released on June 4, 2007 in the United Kingdom and June 5, 2007 in the United States, Systematic Chaos was the band's first release through Roadrunner Records. The album was recorded from September 2006 to February 2007 at Avatar Studios in New York City, after the band's first break from summer touring in ten years. The lyrics of the album were written by John Petrucci, James LaBrie, and Mike Portnoy about fictional, political, and personal topics, respectively.