I remember when I was younger (around 2008-2012) I used to read a lot of "classic" science fiction. Isaac Asimov, Larry Niven, etc. This was either a short story perhaps published as part of a collection, or less likely a small section of a larger novel.
The setting was a modern academic one, perhaps a college or university campus. Some of the students there have basically invented a Star Trek-style matter replicator/molecular assembler. One of the students wants to prove a point to a specific professor, so they steal that professor's Stradivarius violin and use the machine to make an exact copy of it. They then replace the professor's Stradivarius with the copy and show up to his lecture the next day with the original.
The student presents the original and tells the professor it is a copy. The professor tries it out, says it doesn't sound authentic at all and nearly smashes it on the ground before the student stops him.