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 its partnership, in November 1993 (fourteen months before the network debuted), Tribune agreed to a deal to affiliate most of its independent stations with The WB. Despite Tribune's minority stake, the company's stations were not considered to be WB owned-and-operated-stations due to Time Warner's controlling interest in the network. This resulted in The WB having the unusual distinction of being the only broadcast network that did not have O&Os in New York City, Los Angeles and Chicago throughout its existence (the three Tribune-owned WB affiliates in those cities – WPIX, KTLA and WGN-TV, respectively – were "affiliates" of the network