When composers score for huge ensembles, how do they manage to keep track of dozens of voices at once?

Question

Examples: Masses/Requiems (Bach, Mozart, Schumann), Scriabin's Mysterium etc.

When I had to write simple four-voice chorales for music theory, I struggled to keep track of all the voices - how is it even possible to know what you are writing sounds like? This is under the assumption that 1) no perfect pitch 2) not at a piano to test chords as you write.

Of course, you write down the chords at the bottom of the staves in roman numerals, but still, it makes my head hurt. Did these composers write down chords in roman numerals as well? Especially for polyphonic works (Bach) - how do you know if the "clash" from suspensions etc are correct? In "Gloria" from Bach's b minor mass, I noticed how when the woodwinds play the opening theme, all four voices are playing distinct "accompaniment". How? That's half a dozen independent voices to keep track off.

Answer 1

Short answer - genius. It takes amazing skill to know when you have too little or too much going on at one time. Some rare geniuses, like Mozart, appeared to just spill it out more or less in its finished perfect form. I believe Bach was like that too. Others had/have to work harder and longer on perfection.

When it comes to hearing what you intend and knowing how to write it, a wonderful example is Britten. He forbade his composition students to 'try things out' on the piano. He insisted they know what they are trying for and accomplish it without use of the piano. That's certainly how he composed.

No one was better at writing multiple voices that miraculously come together to form something even greater than JS Bach. There are examples of incredible clashes in his writing that look terrible on paper but that are all the more amazing when heard. He broke the rules with unique and wonderful results.

Stravinsky wrote for huge forces but his genius enabled him to create extraordinary soundscapes with just the right amount of activity on the score. His scores can look terrifying, but the result speaks for itself. It takes genius to control and mould these huge forces.

Answer 2

The brain mirrors sounds it knows well. If I lose my voice, I won't have trouble reading and imagining how words sound.

In my own experience, when I'm really composing a lot, I find that I can really hear the sounds in my imagination, like that famous scene in Amadeus. Some people are like that all the time-- for me it's only when I've been working hard, and probably about 20 cups of coffee into the process. :D

Me when my composition homework was due:

This is literally the movie moment that made me go into music school. I had to practice piano 8 hours a day to get in, and in the end they made me a theory major anyway. Best failure of my life!