Piano key sounded like a guitar string on top of regular piano timbre?

Question

No, this isn't an electric piano that I set to piano + guitar.

This is the same upright piano that I have played on for years.

While I was playing Fur Elise, specifically the section with no left hand rests, I heard a twang coming from one of the keys, not sure which one but I am pretty sure it was in the treble clef, specifically either the high end of the first octave or the low end of the second octave.

It sounded like a guitar string was plucked hard at the same time that a key at the same exact note was pressed at forte.

Does that mean that I just broke a string on the piano? And if so how could I tell, lack of note when I press a key?

Answer 1

You could always open the top and have a look ! It sounds like a string has broken, but, because there are three strings on the top couple of octaves, and two on the next few, the note will still play, although a certain richness will now be lacking.

It's surprising that the broken part isn't catching on any other strings, making even stranger noises.