FRESH from directing a performance of Monteverdi's 1610 Vespers in New York, I was a little surprised to read in Roger Bowers's article in last November's Early Music that downward transposition by a 4th of its high-clef movements was supposedly no more than ‘theoretically’ possible. While Bowers argues that ‘the properties of the music itself deny its applicability’, my own recent experience (with both Lauda Jerusalem and the Magnificat a7 down a 4th) had been of an ease and naturalness that seemed to render further theoretical justification wholly unnecessary. Bowers wholeheartedly accepts the need for downward transposition; it is the appropriate interval of transposition that he calls into question. Where I have long advocated downward transposition of a 4th (↓4th), Bowers now proposes a whole tone (↓2nd).

This turn of events – somewhat unexpected after two decades – has had the entirely healthy effect of sending me back to my original Early Music article, as well as to a pile of notes on subsequent findings. Rather than delay in order to accumulate yet more material (while readers mislay their copies of Bowers's article, forget the details of its contents or simply lose interest), I have chosen to respond swiftly and as succinctly as the subject permits, focusing on the Magnificat a7. The present contribution therefore reiterates very little of my previous article and should be regarded as supplementary to it. New material is marked with an asterisk (*).

Revisiting the subject in this way and with the benefit of others’ more recent research into related matters of mode has left me with a much clearer understanding of certain critical points. As a consequence I am now distinctly more confident than before that the only plausible transposition for these high-clef movements really is ↓4th. Attractive though Bowers's suggestion may appear, I can discern no basis for it in the practice of Monteverdi's time. Even though I argue for its rejection, my hope is that the reasons for doing so will help clarify an issue which has ramifications far beyond this one publication and its composer.