by whom was this ensemble developed?
Mendelssohn.
String quartet
Further expansions have also been produced such as the String octet by Mendelssohn. 
which of the following was not a member of seato UNANSWERABLE what is the southeast asian treaty organization? It was an international organization for collective defense in Southeast Asia. when was this founded? September 1954 does it maintain an army? Yes, but it quickly became insignificant militarily, as most of its member nations contributed very little to the alliance. what is its culture? It's member states worked on improving mutual social and economic issues. who were the members? Australia, New Zealand, Pakistan, the United Kingdom, etc. where is the first nation located? In the Australian continent. who were the early settlers here? Indigenous Australians what are the famous delicacies of this place? The influence of Asian cultures has led to Australian variants of their staple foods, such as the Chinese-inspired dim sim and Chiko Roll. Vegemite and pavlova. what is the climatic condition like here? It is significantly influenced by ocean currents, including the Indian Ocean Dipole and the El Niño–Southern Oscillation. what is the population here? It has an average population density of / 7682300 round 1 persons per square kilometre of total land area. what are the cultural aspects of this place? Since 1788, the primary influence behind It's culture has been Anglo-Celtic Western culture, with some Indigenous influences. what is the former culture? The culture of British and Irish people. and the latter? It is the heritage of social norms, ethical values, traditional customs, belief systems, political systems, artifacts and technologies that originated in or are associated with Europe. what is its influence on songs ? The solo piano, symphony orchestra, and the string quartet are also significant musical innovations of the West. what is the last one? A musical ensemble consisting of four string players – two violin players, a viola player and a cellist – or a musical composition written to be performed by such a group. what are its various types? String octet
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String quartet [SEP] Variations of string quartet
Many other chamber groups can be seen as modifications of the string quartet: Further expansions have also been produced such as the String octet by Mendelssohn. Notably, Schoenberg included a soprano in the last two movements of his second string quartet, composed in 1908. This instrumentation of adding a voice is succeeded by Milhaud, Ginastera, Ferneyhough, Davies and many others. Another variation on the traditional string quartet is the electric string quartet with players performing on electric instruments.