@techreport{oai:ipsj.ixsq.nii.ac.jp:00096803, author = {松村, 崇志 and 井上, 真郷 and Takashi, Matsumura and Masato, Inoue}, issue = {13}, month = {Dec}, note = {平均律,純正律は音律 (音楽で使われる音の周波数比の決め方) の一種で,代表的な楽器はそれぞれピアノ,バイオリンである.何れも基準音 (ピアノでは 88 鍵盤の中央近くのラの周波数を 440Hz としたりする) に対して相対的な周波数比により各音の周波数を定め,平均律の場合は 「半音上がる毎に 2 の 1/12 乗倍」 と,無理数を用いて決める.一方純正律は小さな正の整数の比を用いるため,和音 (異なる高さの音を複数同時に鳴らす) の構成音が調和してうなりのない美しいものとなる.しかし,純正律はハ長調などの調毎に周波数比率が異なるため,ピアノなどの演奏中に再チューニングが出来ない楽器では,転調が出来ないという欠点がある.本研究では matching pursuit とピアノの特性を利用して,一つのピアノで演奏された楽曲の録音データを純正律で演奏されたような楽曲に変換する手法を提案する.これにより平均律楽器の表現の幅が広がる事が期待できる.結果,時間-周波数スペクトルを期待通りに変換でき,音楽経験の乏しい人でも違いを聞き分けることが出来た., Both 12-tone equal temperament and pure intonation are musical temperaments, the representative examples of their instruments are pianos and violins, respectively. In both temperaments, the frequency of the standard tone A near the center of a keyboard is set to 440Hz. In the equal temperament, the frequency ratio of every neighboring semitones is set to 2 to the power 1/12. On the other hand, in the pure intonation, the frequency ratio is set to the fraction of small positive integers. According to this feature, chords in pure intonation are usually more beautiful than ones in equal temperament. However, pure intonation has disadvantages; the frequencies of tones depend on the tonality of a music and just-in-time re-tuning at every modulation is not a realistic idea for fixed-tone instruments, e.g., pianos. In this report, we suggest a method to translate the recorded sound data of a piano solo play (of course in equal temperament) into ones in the pure intonation. In this method, we utilize the matching pursuit algorithm and some characteristics of pianos. As a result, the change of time-frequency spectrum was as expected. Moreover, the change of hearing impression was somewhat obvious even for musical novices.}, title = {平均律音楽の純正律化―ピアノソロでの試み―}, year = {2013} }