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"Thiele/Small" commonly refers to a set of electromechanical parameters that define the specified low frequency performance of a loudspeaker driver. These parameters are published in specification sheets by driver manufacturers so that designers have a guide in selecting off-the-shelf drivers for loudspeaker designs. Using these parameters, a loudspeaker designer may simulate the position, velocity and acceleration of the diaphragm, the input impedance and the sound output of a system comprising a loudspeaker and enclosure. Many of the parameters are strictly defined only at the resonant frequency, but the approach is generally applicable in the frequency range where the diaphragm motion is largely pistonic, i.e. when the entire cone moves in and out as a unit without cone breakup. Rather than purchase off-the-shelf components, loudspeaker design engineers often define desired performance and work backwards to a set of parameters and manufacture a driver with said characteristics or order it from a driver manufacturer. This process of generating parameters from a target response is known as synthesis. Thiele/Small parameters are named after A. Neville Thiele of the Australian Broadcasting Commission, and Richard H. Small of the University of Sydney, who pioneered this line of analysis for loudspeakers. ==History== The 1925 paper of Chester W. Rice and Edward W. Kellogg, fueled by advances in radio and electronics, increased interest in direct radiator loudspeakers. In 1930, A. J. Thuras of Bell Labs patented (US Patent No. 1869178) his "Sound Translating Device" (essentially a vented box) which was evidence of the interest in many types of enclosure design at the time. Progress on loudspeaker enclosure design and analysis using acoustic analogous circuits by academic acousticians like Harry F. Olson continued until 1954 when Leo L. Beranek of the Massachusetts Institute of Technology published ''Acoustics'', a book summarizing and extending the electroacoustics of the era. J. F. Novak used novel simplifying assumptions in an analysis in a 1959 paper which led to a practical solution for the response of a given loudspeaker in a box, and also established their applicability by empirical measurement. In 1961, leaning heavily on Novak's work, A. N. Thiele described a series of sealed and vented box "alignments" (i.e., enclosure designs based on electrical filter theory with well-characterized behavior, including frequency response, power handling, cone excursion, etc.) in a publication in an Australian journal.〔Thiele, A. Neville (1961). "Loudspeakers in Vented Boxes," ''Proceedings of the Institute of Radio Engineers, Australia'', 22(8), pp. 487-508. Reprinted in ''Journal of the Audio Engineering Society'', 1971, 19(5 & 6), pp. 382-392 & 471-483. Reprinted in R.E. Cooke (ed.) ''Loudspeakers, An Anthology, Vol. 1 - Vol. 25 (1953-1977)'', Audio Engineering Society, New York, 1978, pp. 181-204. Reprinted in ''Vented Loudspeakers - An Anthology'', Institute of Radio and Electronics Engineers. Reprinted in German as "Lautsprecher in ventilierten Gehäusen (Die Berechtnungsunterlagen für Baßreflexgehäuse)," Hifiboxen Selbstgemacht, Elrad extra 8, Verlag Heinz Heise GmbH & Co. KG, Hannover, 1989, pp. 91 - 112.〕 This paper remained relatively unknown outside Australia until it was re-published in the ''Journal of the Audio Engineering Society'' in 1971. It is important to note that Thiele's work neglected enclosure losses and, though a breakthrough at the time, his alignment tables now have little real-world utility. Many others continued to develop various aspects of loudspeaker enclosure design in the 1960s and early 1970s. From 1968-1972 J. E. Benson published three articles in an Australian journal that thoroughly analyzed sealed, vented and passive radiator designs, all using the same basic model. Beginning June 1972, Richard H. Small published a series of very influential articles in the ''Journal of the Audio Engineering Society'' restating and extending Thiele's work. These articles were also originally published in Australia, where he had attended graduate school, and where his thesis supervisor was J.E. Benson. The work of Benson and Small overlapped considerably, but differed in that Benson did his work using computer programs and Small used analog simulators. Both researchers analyzed the systems including enclosure losses. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Thiele/Small」の詳細全文を読む スポンサード リンク
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