Hopefully, after considering the guided listening from the previous section, you already know that any instrument can play the melody; however, each and every instrument have their own set of strengths and weaknesses that can be a challenge for beginning composers.
You might remember learning earlier that it’s difficult for an oboe to play softly in the bottom of its range. In truth, learning the idiomatic differences between the instruments is crucial when composing for a mixed ensemble. Let’s look at the french horn as a case study:
Most commonly, french horns are tuned to the key of F. This means that their music is written a perfect fifth higher than it sounds and that the open notes align with the F harmonic series as written below:
As with most brass instruments large leaps and angular lines (melodies with mostly skips and leaps) are difficult. High notes require some preparation and are tiring over long periods of time. It’s inadvisable to have french horns enter in the highest or lowest parts of their range, and it’s also important to note that the lower part of the range can easily be lost in large ensembles while the higher parts of their range can soar triumphantly over an entire orchestra.
With all that in consideration, a melody like the one below would not be best suited for a french horn: