The GB Sounds allows you to listen to certain music in the game in a whole different game. It lets you listen to what I believe what the music in the area would be like in Gold, Silver, and Crystal.
"A music player that allows you to listen to nostalgic songs. It's operated with a single switch."
The following tells you how to obtain the GB Sounds.
[Note that you must have 16 Badges in order to get this.]
|GB Sounds||Go inside the Celadon Condominiums in Celadon City. Take the elevator on the first floor and pick the option to go to 3F. Talk to the man in front of the globe and he will give you the GB Sounds.|