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 WB); WWOR-TV (channel 9) in Secaucus, New Jersey (part of the New York City market) and KCOP-TV (channel 13) in Los Angeles were de facto O&Os prior to Viacom's buyout of Chris-Craft's stake in UPN, while WPWR-TV (channel 50) in Chicago was an affiliate of UPN throughout the network's run (and would not be co-owned with the two other larger-market stations until after Fox purchased it from Newsweb Corporation in 2002). In September 2006, these stations became O&Os of MyNetworkTV, which was created in response to The CW's decision to affiliate stations owned by Tribune Broadcasting and network part-owner CBS