24 Microtonal Studies for trumpet were written as first material for the replaceable valve mechanism microtonal trumpets developed by Stephen Altoft (although the first five to ten studies can be played on a standard trumpet as is described in the blog Developing the Microtonal Trumpet and its Pedagogy).
- demand increasing fluency and agility in microtonal playing
- are accumulative in terms of complexity of fingering, the use of intervals and music reading
And, of course, they can also be used as concert pieces in any grouping as they have been by Stephen Altoft, Bruce Nockles (who first-performed the first 10 studies) and Sebastian Meyer.
They comprise 16 quarter-tone studies; 4 eighth-tone studies and 4 19-division studies.
The sixteen quarter-tone studies include all possible 24-div intervals up to the octave as well as a number of compound intervals (these are reserved for the higher-number studies). They are planned to emphasise small intervals initially, with wider intervals being introduced sparingly and with musical consideration: there are more smaller intervals than wider intervals overall, a sensible rule-of-thumb for trumpet writing. The complete quarter-tone chromatic range is represented and there is a balance of 24-div and 12-div pitches, in other words as many quarter-sharps or quarter-flats as 12-div sharps/flats and naturals.

The above extract from Study 1 demonstrates the modest start of the studies. If you compare this to learning a piece in standard 12-div it raises a number of questions both for the composer and the player. The first is how to notate the quarter-tones. There are precedents of course, plenty, but little consensus. The signs we chose are ones which are available in music engraving software programmes and quarter-tone signs which allow further modification to become eighth-tone signs. We explicitly chose not to have ‘double signs’ (two signs together, one acting as modifier).

We also made the interim decision not to use the modifying eighth-tone ‘arrow’ on three-quarter sharp or flat signs to try to minimalise perceptual difficulties (eighth-sharp three-quarter-sharp). However this question is also related to enharmonic considerations: the first note of Study 1 could, for example, have been written as an ‘a’ quarter-sharp although this would further disguise the fact that this first interval is a minor third. It was because of the somewhat disorientating appearance of certain spellings that we designed Interval Look-Up Charts for 19-, 24- and 48-div which can be freely downloaded from Microtonal Projects’ website.
Aural example: Study No.15 (extract) Study 15 is the penultimate study and reflects its position both musically and technically. It uses the complete range (previous studies use carefully worked out partial ranges based on technical difficulty) and has an even spread of pitches throughout the range, using more compound intervals than previously. A particular musical feature of this study is to contrast lower-register material with higher register material in the manner of a dialogue.
It is not possible to make an eighth-tone valve using the same design as the quarter-tone valve because the tubing becomes impossible to bend. Eighth-tones are produced, in most cases, with the slides regardless of whether a fourth valve is available (although many are easier with a quarter-tone valve). Although it is technically possible to lip most eighth-tone intervals this is tiring and difficult at speed and in the upper register, the use of the valve slides is more difficult because the amount of adjustment is minimal. The four eighth-tone studies are, then, rather tentative by comparison with the quarter-tone studies, particularly the later quarter-tone studies. However, similar consideration was given to design, interval structure and interval recurrence as in the quarter-tone studies. The following audio extract demonstrates some of the possibilities: in Study 17 the idea was to elaborate on a simple motive outlining a major third, first in quarter-tones then in eighth-tones, while simultaneously varying and expanding the musical cell.
Both the above recordings are by Stephen Altoft, from his CD 24 Microtonal Studies for Trumpet – these are now available as downloads from Tutti.co.uk or Bandcamp.
The 4 19-div Studies will be discussed in a future article following a fuller introduction to this particular tuning system.