Ive been doing some searching and everybody keeps talking about adaptors (2.5mm to 3.5mm). What are they for? I used my headset from my samsung a-900 and it worked fine. I can hear music from both sides, and can answer and hang up calls from the button on the cord. I did notice that it has 3 black rings on the metal tip, where the stock headset only has 2. Whats the difference?

3.5mm is the standard audio adapter size - if you're an audiophile or if you are overly concerned about audio quality, you would much rather buy standard-sized headphones (or you might already have a pair) - say a Shure or Etymotics. These go for $300-600 a pair, so it's a lot cheaper for you to buy an adapter and use the high-quality headphones everywhere - in your home on the high-end audio system or your Pearl.