In order to play the trumpet (or any musical instrument, for that matter) successfully and at a high level, the brain has to effectively maintain control and co-ordination of many physical and mental variables, most often in a manner synchronous with a given pulse.
When reading from music, the first job is quickly decoding the symbols on the page just prior to playing the note or phrase. For us to play the music correctly, this initial process must continue working in the background. This in itself requires unbroken concentration. When playing begins, other factors become included, such as timing and measuring of inhalation, maintaining and adjusting breath support in relation to dynamics, deciding and delivering the fine control messages to the muscles surrounding the tongue, jaw, oral cavity and lips to pronounce the desired articulation of notes and modulations of tone colour. In addition, the fingers have to operate the valves securely and timely for us to change smoothly from note to note in synchronisation with our articulations. To be successful, all this has to occur in a manner relative to our internal (or external) musical pulse.
In my experience, a faltering of any one of these factors can have a sometimes surprising and subconscious negative effect on another. For example, your tone quality can suffer from losing the sense of pulse in a phrase. You might think your lips weren’t set right for a particular note, when in fact, your late and shallow breath was the culprit. There are endless examples of these correlations, but I believe the fingers to be the worst culprit in bringing things to a standstill.
As a trumpet player, have you ever noticed that you feel like you can produce a better sound playing major scales such as C, F or G, whereas it just seems a little harder to be open and beautiful on maybe A, B or C#? I believe this is down to the control of our fingers taking attention away from the processes that truly matter for producing a good sound, such as relaxed breathing and proper and consistent airflow. I believe that by working the fingers separately so that they become more habitual and nimble allows you to ‘forget’ about them more, if you like, and devote more time to producing that beautiful tone.
I’ve effectively employed this approach many times in my teaching. Try it next time you or a pupil come up against a phrase or scale that you’re not quite nailing. When you see a pupil mindlessly fumbling through a scale, making mistake after mistake with a suffering tone, tell them to sing the scale while just pressing the valves (or if they’re a bit self-conscious, you can play the scale whilst they do the fingerings). Work on this until they have ironed out their little mistakes and are completely confident with the fingers. Then get them to play the scale. 99% of the time, they will play it not only correctly first time, but with a nice controlled sound right up to the top and back down.
The reason why this works so well is that when you remove the other tasks and just focus in on one aspect of technique, it can be mastered and shelved a lot more quickly than just fumbling through the thing mindlessly. Also, I feel that, with the fingers being so thoroughly and deeply connected to a large area of our sensory and motor cortex, they literally take up a lot of brain power when trying to navigate dexterously challenging passages of music. The more effectively you program your brain to habitualise these complex movements (which can essentially become barriers to us playing certain things), the more you can ‘forget’ them and concentrate on the good stuff.
I work a lot on my finger technique and my gains in proficiency in this area have gone hand in hand with my being able to produce and maintain a good sound when playing difficult and awkward passages.