Are their instruments are wood or metal of Javanese and Balinese?

The instruments of Javanese and Balinese gamelan are primarily made of metal, with some exceptions for wooden components. Here's a breakdown of the materials used in Javanese and Balinese gamelan:

Metal:

- Saron: A set of metallophones made of bronze, with keys arranged in a horizontal row.

- Demung: Another set of bronze metallophones, slightly larger than the saron.

- Slenthem: A set of bronze bars suspended horizontally, played by striking them with a mallet.

- Gender: A set of bronze gongs, graduated in size and tuned to specific pitches.

- Kenong: A set of hanging gongs, smaller in size compared to the gender.

- Gong ageng: A large hanging gong, usually the lowest in pitch in a gamelan set.

- Kempul: A small hanging gong, used to mark the beat or provide punctuation.

Wood:

- Rebab: A bowed string instrument with a wooden body and a single or double string.

- Suling: A bamboo flute, played by blowing into a mouthpiece near the side of the tube.

- Kendhang: A double-headed drum with a wooden body, played with the player's bare hands.

- Gambang: A xylophone with wooden keys, suspended on a wooden frame.

Other components of the gamelan, such as the wooden frames and resonators, are also made of wood.

It's worth noting that while most gamelan instruments are crafted from metal, some regional variations may include additional wooden instruments or variations in material choices.