OK, this isn’t going to win any Grammies anytime soon, but I whipped up some examples quickly in Garage Band. Forgive the cheesy quality of the sounds and the recording, but it should help illustrate what I’m talking about.
I’ve used “Can’t Help Falling in Love” as my example.
Here it is in 12/8 time. (How Elvis recorded it.)
Here it is with a 3/4 feel. (Sorry, there’s a little bit of silence I forgot to delete from the beginning here.)
The 12/8 and 3/4 example have exactly the same organ melody line. I literally cut and pasted the 12/8 example into the 3/4 example. I just played drums and piano with a different feel under the melody line so you can hear the difference.
Here it is with a true 4/4.
And, just for fun, here’s what it might sound like in 5/8.