Sometimes we think of ourselves as being able to hear an entire complex musical texture at once holistically, as a “Gestalt.” This, for example, is what a conductor uses when noticing the one wrong note in a chord that involves many instruments playing different notes—it’d be incredibly time-consuming to listen individually to each different one!
Nevertheless, we are not able to focus on everything in a texture equally all at once. In sight, our visual attention has a primary focus, but there is also a broader visual field that our eyes and brains are aware of in less detail. As long as that visual field seems mostly familiar, our brains are pretty good at filling in the details and noticing surprising elements, but if what we’re looking at is confusing and unfamiliar, we may only be truly aware of whatever we’re focusing on. It seems like hearing is similar: as one scholar says, “the data suggest that the pitches of many tones can be processed simultaneously, but that listeners may only be consciously aware of a subset of between three and four at any one time” (Oxenham 2013, 21).
How can you get better at listening to a whole ensemble or complex texture and figuring out what is going on? The best way is to give your brain lots of models by learning lots of music in a style similar to what you plan to listen to. For example, if you aim to be a band conductor, learn lots and lots of band music. Your brain will use its memories of other pieces it knows to fill in details of the parts of the sound it isn’t focused on, and the more models it has, the better it will do.