Pretty sure the answer is just "40 minutes" and it is a question to make someone think about what they are doing rather than automatically solve every task.
Reminds me of an animator saying ''If a pregnant woman takes nine months to have a baby, can four women have a baby in two and a half months?''
The point is, somethings can't be done faster through simple numbers. Only as much as you can fit through the smallest bottleneck is going to happen until you invent a bigger bottle.
Most speedrunners know about the glitch in Beethoven's 9th where if you have the entire brass section make a quarter turn to the left at just the right moment of the open fifths the whole symphony freezes for a second and then drops you straight into the Ode to Joy.
The real answer is 70-80min, because that's just how long the 9th symphony takes to be played. And they better add a chorus as well, otherwise the 4th movement won't be as good as it normally is
Let’s say you put like 1000 violinists all in a big, long row. Then, have the first violinist play a note, then the second plays the very same note, then the third, and so on. Let’s say you could also time it so that at the very moment the sound wave from one violinist hits the next is when that one plays the note. Brrrrrrump! All the way across. Let’s also say you could time it perfectly so that the waves don’t cancel each other out. What would happen?
As I was going to St. Ives I met a man with seven wives. Each wife had 7 sacks, each sack had 7 cats, each cat had 7 kits. Kits, cats, sacks, wives; how many were going to St. Ives?
We need a player for every note in the score(tied notes can be played by a single musician). On the conductor's downstroke everyone plays their note. Every note of the 9th played simultaneously. I want to hear this, but I don't think that my poor old computer would function if I opened that many individual instruments in Reason.
Just put the orchestra on a spaceship approaching light speed, and you can take even less time (relatively experienced by an off-spaceship audience.) If you still want the shockwave, you can use an Alcubierre drive.
The answer could be however many beats the longest note is at however many BPM you choose given that 60 is a large enough number to cover each pitch and quality of note in the piece. Having all the essential notes and durations covered, the rest is just inessential noodling left as an exercise for the reader.