Gamelan Online: Virtual Saron and Demung
Gamelan is the bronze percussion ensemble of Java and Bali, built mostly from metallophones and gongs, and it has been on UNESCO's list of Intangible Cultural Heritage since 2021. This gamelan online page gives you two of the Javanese gamelan's keyed instruments: on top, a saron barung with 7 keys tuned to slendro (6̣ 1 2 3 5 6 1̇); below it, a demung with 7 keys tuned to pelog (1 to 7), an octave lower. There is no bonang, kenong, gong or kendang here: just saron and demung.
How to use it
- Tap the keys with your fingers; you can hit several at once or slide across them. On a computer, use the mouse.
- On your computer keyboard, Z X C V B N M play the pelog demung from 1 to 7 and Q W E R T Y U play the slendro saron: 6̣ 1 2 3 5 6 1̇. Esc stops every sound.
- In the labels menu, show the kepatihan numbers, the keyboard letters or nothing.
- Tap Record, play, then tap again to stop. Then use Play, ↓ MIDI, ↓ WAV or Share.
- The full-screen button makes the keys bigger; on a phone, turning it sideways helps.
Help and explanations
The sound is synthesized on your device, not recorded from a real gamelan. It models a bronze key: a long fundamental with a slow beat and the dry knock of the wooden mallet (tabuh). You can strike several keys at once, record what you play, download it as WAV or MIDI and send a link that carries the notes.
Slendro and pelog
Slendro has five notes per octave in almost equal steps of about 240 cents (a piano semitone is 100), so it has no 4 or 7, and the saron runs from 6̣ (the 6 of the lower octave) up to 1̇. Pelog has seven notes with uneven steps; here, counting from 1, they sit at 0, 120, 258, 539, 675, 785 and 943 cents. The saron's 1 sounds near 587 Hz, and the demung's 1 an octave below.
These are rough averages: every gamelan has its own tuning (embat), and there is no single table for slendro or pelog. A real gamelan has a separate set of instruments for each tuning; here the two sit side by side so you can compare them. Since this isn't piano tuning, there are no chords, scales or note challenge.
Reading kepatihan notation
Javanese gamelan is usually written in kepatihan, a number notation: each number is a key, a dot above raises it an octave (1̇) and a dot below lowers it an octave (6̣). A dot on its own in place of a number is a beat with no stroke. Notes come in groups of four beats called gatra, and the strongest beat is the last one in each group.
The saron plays the balungan, the skeleton melody that the other instruments decorate. To start, read two gatra slowly on the saron: 2 1 2 6̣ is E W E Q and 3 5 3 2 is R T R E.
Pieces to practice
To start, look up the balungan in kepatihan for Lancaran Manyar Sewu (slendro, pathet manyura) or the songs Gundul-Gundul Pacul and Suwe Ora Jamu, all common beginner pieces, and type each gatra onto your keyboard. Since every gamelan has its own embat, a melody may sound a little different from the recording you know.
Tips
- On a real saron the other hand damps the previous key; here each key rings until it fades, so play slowly to keep the balungan clear.
- Compare 1 2 3 on the saron with 1 2 3 on the demung: slendro steps are nearly equal, while in pelog the 1–2 step is very small.
- Headphones or an external speaker help you hear the slow beat of the demung's low keys.
- For melodies in piano tuning, try the online xylophone.
Frequently asked questions
Why does the gamelan sound out of tune next to a piano?
Slendro and pelog don't use the piano's 12 equal semitones. Slendro splits the octave into five steps of roughly 240 cents, and pelog has seven notes with uneven steps.
Is this the tuning of a real gamelan?
It's an approximation built from averages. Every gamelan has its own tuning (embat), and two sets can sound quite different, so there's no official table.
Does it include bonang, gong or kendang?
No. The page has only a slendro saron barung and a pelog demung, the keyed instruments that play the balungan.
Can I record and share what I played?
Yes. Record, stop and tap Share: the link carries the notes in the address. The WAV keeps the sound as you heard it; the MIDI file uses the nearest piano note for each key, so it's only approximate.