I've been trying to find out the name of this type of instrument. It is at the beginning of the song "just let go (album version)" by Fischerspooner and a few other people. i know that you hold down however many notes you want to here and it plays them in a random order. any help would be great.

hey there, i don't know that song , but you are describing a feature called ARPEGGIO , that most synths have ... so its not any peticular instrument, just go around and look for synths with that function.