In a previous post I looked at playing 19 equal divisions of the octave on my horn with a modified stopping valve slide. My composition Epictetus The Younger uses a few pitches from the 36-division equal system. This piece is for standard B-flat trumpet and piano and can be played by French horn and piano.
The usefulness of this 36-division system is that there are 12 notes in common with a standard tuned piano. The usefulness of this for brass player is being able to play in duet with a pianist. This is also useful for students who may wish to begin exploring microtonality and have easily accessible reference pitches. Often students in their last year or two of high school find it musically rewarding to work with a pianist and ofter that pianist is a professional musician, and often of high calibre. Microtonality without easy reference pitches can be quite daunting. Of course, compositions can include computer generated music. Having another musician to work with can be a rich and wonderful experience, hence my interest in combining a pianist along with the microtone-producing musician.
It seems worthwhile to consider playing all 36 notes on the horn.
I currently have two instruments with stopping valve. One is a B-flat single, the other a full double horn in F and B-flat. Both now have short slides attached to the stopping valve. The slides are short enough to produce reliable quartertones and can be easily extended to give the longer (63cent) semitone for 19 equal divisions. Neither slide can provide the 33cent step but can provide the 66 cent step.
The way to provide the 33 cent step is to sue the double horn and tune the entire F horn lower by 33 cents. The B-flat horn provides all the tones and semitones of the 12 equal divisions, and the short slide the steps that are 66 cents lower.