So the coolest thing happened to me on the way to the store today, my ‘22 Mazda 3 hatch’s exhaust note harmonized with the note an NA Miata some dude in the lane beside and about one car length behind me was driving! I was in sport mode and just cruising down this 1.5 mile straight and all of a sudden there was this incredible sound resonating through out the car. It only lasted for a few seconds and I know they harmonized because whenever one of us would speed up or slow down a little the sound would stop and then start when we crossed the right distance from each other.
I mean I understand the physics around acoustic harmonics but experiencing that in the real world is next level, I doubt if I’ll ever experience something like that again but it was cool while it lasted!
They’re similar engines, one is 2.0 and one is 2.5, to be expected.