ABSTRACT
One of the unique aspects of Bach's Wohltemperirtes Clavier (WTC) is the reference to tuning contained in the term wohltemperirt. From the second half of the eighteenth century well into the middle years of the twentieth century, it was generally agreed that wohltemperirt meant 'equal-tempered'. The WTC was considered to be one of the first examples of what could be done with the tonal system when all twelve semitones were of equal size, so that all keys sounded the same. Only Barbour (1947 p. 69, and 1951 p. 195) was a little less sure about the unquestioning identification of 'well-tempered' with 'equal-tempered'. He remarked that since Neidhardt (1706) the Germans had used the term gleichschwebend ('equal-beating') to mean 'equal-tempered', and that Das Wohltemperirte Clavier might possibly been better translated as 'The Well-Tuned Piano'. He explained 'well-tempered' as a term implying that all keys can be played, with the common ones (the 'central' or 'diatonic' keys, with only a few or no sharps or flats) sounding better than the uncommon ones (the 'chromatic' or 'peripheral' keys, with many sharps or flats). All this was prompted by a quotation from the Hodegus curiosus of Werckmeister (1687).
