“Gamelan gets its name from the low Javanese word ‘gamel’, which means a type of hammer, like a blacksmith’s hammer. The name ‘gamelan’ refers to the method of playing the instruments - by striking them - as they are almost entirely percussion.”

(Lindsay, J. (1979). Javanese Gamelan. Oxford: Oxford University Press, p.9)

Kendang - drums
The kendang is the rhythmic leader of the group.

The kethuk, kempyang, kenong, kempul and gong support the kendhang in defining the structure and setting the speed. Their names are onomatopoeic; the names sound like the sounds made by the instruments.

The slenthem (left) and saron (right) play the balungan - the skeleton of the melodic line. The saron family includes the saron panerus (the smallest member), saron barung (middle-sized) and demung (the largest member).

Bonang
The bonang plays an elaboration on the melodic line. It acts as the melodic leader in ensembles of the louder instruments.

Elaborating instruments

The gender, rebab, gambang, suling and celempung, also elaborate on the melodic line. They are used in an ensemble of softer instruments and in quieter pieces. The gender or rebab acts as melodic leader in such ensembles or pieces.
The gambang is the one instrument in the ensemble with wooden keys.

Voices (sindhen and gerong)
Singers have a role in gamelan that is comparable with other instruments. The singers are usually organised as a solo female voice (pesindhen) and a male chorus (gerong).

(based on Wikipedia entry)

• Pokok instruments - these instruments play the core melody
  • jublag - medium pitched, 5-keyed bronze metallophones
  • jegogan - low-pitched, 5-keyed bronze metallophones

• Punctuating Instruments
  • kempli - small gong on a stand; keeps the beat.
  • gong - largest suspended gong (sometimes two are used) (G in notation)
  • kempur - medium-sized suspended gong (P in notation)
  • kemong (also called klentong or kenong) - small suspended gong (T in notation)

• Elaborating Instruments
  • gangsa - the group of bronze metallophones that play most figuration and faster melodies, consisting of:
    • kantilan (small, high-pitched);
    • pemade (medium-pitched);
    • ugal (low-pitched) (usually taller and may play solo passages)

• reong - a row of 12 tuned gong chimes that play either interlocking melodic figuration or rhythmic parts together with the drum and ceng-ceng

Reong

• Rhythmic Instruments
  • kendang - drums—higher pitched kendang lanang (female); lower pitched kendang wadon (male)
  • ceng-ceng - cymbals on a stand (often shaped like a turtle)

“The bronze gamelan instruments are made from a mixture of copper and tin; three parts tin to ten parts copper.” (Lindsay,1979, p.19)

The bronze is forged in fire.

Each set of gamelan instruments is tuned slightly differently from each other as there is no standard reference point (such as A440) in gamelan music. None of the tunings match a western diatonic scale.

In a complete set of Javanese gamelan, there are two tuning systems called pelog (7 notes) and slendro (5 notes). In West Java another ensemble called gamelan degung (also known as Sundanese gamelan) has its own 5 note pelog tuning system.

In Bali, pelog tuning predominates with ensembles such as Gong Kebyar using a 5 note pelog system and Semar Pegulingan using 7 notes. Balinese Gender Wayang ensembles, played in shadow puppetry, use a 5 note slendro scale. A feature of Balinese tuning is to tune pairs of instruments slightly apart so that when played together, the sound ‘beats’, creating the characteristic shimmering sound.