Polyphony and monophony in instruments harpejji and the Chapman stick). Multiphonics can be used with many regular wind instruments to produce two or more notes at once, although this is considered an extended technique. Explicitly polyphonic wind instruments are relatively rare, but do exist. The standard harmonica can easily produce several notes at once. Multichambered ocarinas are manufactured in a number of varieties, including double, triple, and quadruple ocarinas, which use multiple chambers to extend the ocarina's otherwise limited range, but also enable the musician to play more than one note simultaneously. Harmonic ocarinas are specifically designed for polyphony, and in these instruments the range
Owned-and-operated television stations in the United States as a result). However, Tribune was the only one of the two companies involved in The WB that owned any stations aligned with the network as Time Warner did not own any television stations at the network's launch and would not own one until its 1996 merger with the Turner Broadcasting System, owners of Atlanta superstation WTBS (channel 17, now WPCH-TV; its national feed, TBS, is now a separate basic cable channel). On January 24, 2006, Time Warner and CBS Corporation announced that they would merge The WB with the CBS-owned United Paramount Network to form a new broadcast network