This Italian harpsichord, which is both unsigned and undated, currently has two sets of 8ft strings and the 50-note compass C, D to d3. Detailed analysis of the instrument by Dr Grant O’Brien, however, shows that it has been the subject of several alterations and that it originally had just one set of 8ft strings and the compass C/E bass broken octave to c3, with some additional split accidentals in the treble to enable the performer to play pieces that modulate to distant keys whilst using a meantone temperament. In addition, O’Brien has shown that RCM0175 has a number of characteristics typical of harpsichords constructed in Naples: these include a sharply-pointed tail; a keyboard that slides in and out like a drawer; case sides that are made from sycamore or maple rather than cypress; and carved keyblocks rather than cheek scrolls. Various other components, such as the style of the soundboard rose, the case mouldings and, most importantly, the unit of measure that was used in its design and construction, have led O’Brien to argue that the instrument was constructed in the workshop of Onofrio Guarracino, who was active in Naples during the second half of the 17th century. Furthermore, O’Brien has calculated that with an original design scaling of 12 Neapolitan inches this instrument was originally intended to sound one whole tone higher than those Guarracino based on a design scaling of 13½ inches. Many harpsichords were updated during the course of the 18th century in response to changes in musical taste. In this case, O’Brien has suggested that the final stage of alterations took place in Florence at the workshop of either Cristofori or his pupil Ferrini. As such it indicates that while split accidentals and a single choir of 8ft strings were considered out-of-date by the early years of the 18th century, the tone quality of Neapolitan instruments must have been deemed worthy of preserving.