What's a Gamelan?:
A Gamelan is a set of instruments that is assembled blessed and then always played together, it is the most popular genre in Indonesia.

Map of the islands:

Cultural notes:
The Gamelan is connected to the religious culture of Indonesia it is blessed before played, and its the basically worst crime there to take an instrument from its Gamelan.

Music characteristics:
Lots of percussion and sometimes flute. Also, gamelan music has lots of overlapping intruments to create an interesting group sound like a orchestra.

Instruments found in gamelans:

How instruments are aranged:

Wikipedia Gamelan
Wikipedia Music of Indonesia

Videos and sound clips:
A gamelan performance:

Some Modern Gamelan music from Calabash: