Gamelan Listrik: A Low-cost Solution to Introduce Javanese

Gamelan to the Young Generation

Petrus Sutyasadi

Politeknik Mekatronika Sanata Dharma, Yogyakarta, Indonesia

Keywords: Gamelan listrik, javanese gamelan, electric gamelan, midi gamelan.

Abstract: This paper offers a new design of electric musical instrument that called Gamelan Listrik. Gamelan Listrik is

designed to be a low-cost instrument that can be used to play Javanese traditional music ensemble. A set of

traditional gamelan instrument is very expensive. This makes only a few elementary schools own gamelan

instrument and causes only a few numbers of students who know the instrument or even able to play it.

Gamelan Listrik is proposed to be the solution of this matter. Using the gamelan Listrik, an elementary school

can develop a gamelan class where the students can learn basic playing of the instrument and gain experiences.

The most important thing is the students will have opportunity to develop their motivation in their early age.

Experiments showed that Gamelan Listrik performed satisfactorily. It has small latency and the sound volume

can be controlled by varying the mallet hitting/striking force to mimic the real gamelan playing. The cost of

gamelan listrik is about 1/10 from the cheapest low quality of real gamelan made of iron, or about 1/100 from

good quality made of bronze.

INTRODUCTION

The word gamelan is derived from the word “gamel”

which means to strike or to handle (Sumarsam,

1988). It refers to a music ensemble of Java or Bali

Indonesia that has metallophones at their core

(Johnson, 2008). Gamelan will produce its tone

when it is struck with mallet except the percussion

called kendhang that played by hitting using our

palm or fingers, zither types of instrument, and flute.

Gamelan is a cultural heritage that should be

preserved. Some researchers mentioned that gamelan

is popular in many countries as an ensemble to be

played (Wardhana et al., 2015). Besides, gamelan

music can be used as a good method to reduce labor

pain (Resna et al., 2017) (Ismail, 2011) until

emotional therapy in prison (Mendonça, 2010).

Nonetheless, only a few people especially in Java

who play gamelan and it became less popular among

the young people (Purbayekti, 2011). Young

generations nowadays are rarely knowing this kind

of instruments because they do not easily meet this

kind of instrument whether at school or at their

neighborhood. There are some reasons that make

gamelan is a bit hard to be learnt (Kurniawan and

Syarif, 2013) (Wijaya, 2015) such as: 1) The size of

gamelan is not flexible, 2) Normally gamelan is

played in team, cannot be played individually, 3)

The price of gamelan set is very expensive, 4)

Gamelan needs a special maintenance, and 5)

Gamelan needs a large of space.

There were some researches tried to overcome

this situation. One method is using tablet or smart

phone installed with application that can produce

gamelan instruments sound (Hesananta, 2018)

(Sumirat, 2014). Other projects are using laptop

instead of tablet or smart phone (Kurniawan and

Syarif, 2013) (Wiriadjaja, 2013). Commonly those

researches tried to produce gamelan sound that can

be played from the device interface whether it is

using touchscreen, button from the keyboard, or any

hardware designed to trigger the sound. All the

projects may have resolved the highly cost, size, and

flexibility problem. However, by using the devices

produced from the researches mentioned above, the

player still loses the real sensation in playing

gamelan since they omit the role of the mallet.

Secondly, the previous researches designed a single

instrument for a single player. It means if we want to

play in group, we need to duplicate the whole device.

Consequently, the cost will increase proportionally.

This paper offers a new design of electric gamelan

that may reduce the learning problems mentioned

172

Sutyasadi, P.

Gamelan Listrik: A Low-cost Solution to Introduce Javanese Gamelan to the Young Generation.

DOI: 10.5220/0008556901720176

In Proceedings of the 1st International Conference on Interdisciplinary Arts and Humanities (ICONARTIES 2019), pages 172-176

ISBN: 978-989-758-450-3

above. It still incorporates the mallet striking so the

player gets the real sensation of playing gamelan. The

design is very efficient in size and price as well. When

playing in group, we just need to duplicate the

embedded system and the gamelan input device only.

While the sound engine still relies on a single PC.

When the student wants to practice in solo, the design

supports individual playing or practice with digitally

pre-programed accompaniment. It can be used as an

alternative method to teach gamelan in school with

many benefits that were not easy to do before.

GAMELAN DESIGN

This section will explain the overall design of the

system including the mechanic, electronic, and

software design. The main block diagram of the

system is shown in Fig. 1 below. Suppose there are

10 instruments, all those instruments are connected

together through a USB hub. The signals from the hub

are sent to the PC or laptop through a USB port.

Kontakt free player is installed in the PC to receive

all the instrument signals that have been mapped to

several midi channels. The midi signals converted to

audio sound by the Kontakt free player software. The

quality of the sound amplifier and the speaker have a

large influence to the quality of the final gamelan

listrik sound.

Figure 1. Block diagram of the system

2.1

Mechanic Design

The mechanical design actually will not be the same

among different instrument. For example, saron and

bonang are physically different in shape, therefore

the design of the instrument is also different. Saron is

made from several metallophones’ plates. To mimic

the plates, we used hard sponge. Mechanical design

of saron is shown in Fig. 2. The thickness of the first

layer of the sponge is 1.2 mm. After the sensor is

attached, we put 5 mm thick hard sponge to cover it.

The next layer should be soft enough so it will not

deliver the vibration from one plate to the others.

Later as the base we use harder material such as

particle board.

Figure 2. Mechanical Design of Saron Listrik

The plates of the metallophones made of rubber

and acrylics. The impact sensor is put in between the

rubber and the acrylics. The upper rubber prevents the

mallet impact noise due to the difference with the real

gamelan where the sound actually produced by the

impact itself.

Figure 3. Prototype example of wilahan and pencon style

In Gamelan Listrik, impact of the mallet and the

instrument does not generate the gamelan sound

directly. Instead, it will generate impact sound

without tone or noise that actually we do not want to

exist. Therefore, we designed the instrument surface

to be soft enough to absorb the impact, but the player

still able to feel the impact. Fig. 3 shows example of

the gamelan prototype.

2.2

Electronic Design

The sound is triggered by the mallet impact to the

metallophone plate. The impact is detected using

piezoelectric sensor. The sensor converts mechanical

force into electric signal. The electric signal is read

by the microcontroller through an analog to digital

converter (ADC). The signal received by the

microcontroller is analog and proportional to the

amount of forces generated by the impact. Therefore,

Gamelan Listrik: A Low-cost Solution to Introduce Javanese Gamelan to the Young Generation

173

we can use the information to control the volume of

the instrument’s sound. The tone and the volume

information will be sent to the PC as a midi signal.

The schematic of the electronic sensor and its signal

conditioning design is shown in Fig. 4 below.

Figure 4. Electronic schematic of the sensor system

2.3

Software Design

Gamelan ensemble normally is played in group, and

we need a good quality of sound to mimic the real

gamelan sound. To manage such things, midi is the

best choice since it is the only standard in digital

music. The individual instruments of gamelan sound

are sampled. The sound was sampled using Kontakt,

an industry standard sampler from Native Instrument

(Native Instruments, 2019). Kontakt can receive

midi signal from several external midi input directly.

Using midi hub, we can connect several midi devices

that has been programmed to produce different

gamelan instrument sound. The block diagram of the

midi devices arrangement and the PC is shown in

Fig. 5 below

Figure 5. Block diagram of midi devices connection to the

TESTING METHOD

After the system fully assembled, there were several

tests conducted to check the performance. We need

to know how close the system performance to the

real gamelan in term of the player experience and

playing sensation. Therefore, some parameters

involved are: latency time, maximum hitting

frequency, and the volume or midi velocity range.

Latency time is measured from the first hit of the

mallet until the particular sound is produced from the

speaker. The struck of the mallet was captured using

piezoelectric sensor and then the signal was sent to

latency test microcontroller. The output from the

speaker was captured using sound sensor and then

passed directly to the latency test microcontroller.

The detected time difference of the two the signals

was measured by the microcontroller and converted

into latency time. Maximum hitting frequency test is

conducted by measuring and logging the maximum

frequency of the mallet strike the metallophone plate

whilst it still produces a true and relevant sound.

While the midi velocity test was conducted by simply

strike the plates in two power variation and plot the

response. The hardware connection for the latency

test, maximum frequency test, and the midi velocity

response test is shown in Fig. 6.

Figure 6. Latency test hardware connection diagram

RESULT AND DISCUSSION

The three tests result are shown in Table 1 and Fig. 7

to Fig. 8. The latency time result is shown in Table

1. The table shows that in average the system has

14.5 ms latency time including around 1ms the cycle

time of the Arduino program as the data acquisition

system. Therefore, the overall latency time from the

mallet striking to the captured sound from the loud

speaker is around 13.5ms. This latency time is

acceptable and the actual sound also gives

satisfactorily result.

ICONARTIES 2019 - 1st International Conference on Interdisciplinary Arts and Humanities

174

Table 1. Result of the latency test in micro second

Latency

(uS)

Latency

(uS)

Latency

(uS)

1 14904

15 14904

29 14896

2 14240

16 14792

30 14896

3 15008

17 14904

31 14680

4 14784

18 22184

32 12320

5 14896

19 14792

33 15016

6 14792

20 18528

34 15288

7 15008

21 14896

35 14680

8 10216

22 14792

36 16448

9 14896

23 14792

37 14568

10 14896

24 14792

38 14784

11 14904

25 14784

39 10624

12 14784

26 16104

40 14904

13 14784

27 14792

41 14680

14 14896

28 14896

42 14784

Average

14539 uS

The maximum hitting frequency is shown in Fig. 7.

The maximum period of the strike before the actual

sound from the speaker overlapped is 149 ms, or the

maximum frequency is 6.7 Hz. This frequency is also

acceptable because there are no high frequency

striking for the basic gamelan training in elementary

school.

Figure 7. Maximum mallet striking frequency on the

metallophone plate

The midi velocity test results are shown in Fig. 8.

Higher power strike is shown with higher amplitude

and the lower power strike is shown with lower

amplitude. From this graph we can set the range of

the midi velocity by mapping the actual analog read

of the mallet strike to the range of standard midi

velocity. This feature is important when we have

vocal singing during the play. Normally when the

vocal start, the gamelan player needs to reduce the

sound volume by reducing the striking power when

playing the gamelan instrument so the vocal can be

distinctly heard.

Figure 8. Analog read of the piezo electric sensor for midi

velocity test.

The Kontakt software is not a freeware. A sampler

or composer software usually is not cheap. However,

any school which want to use the Gamelan Listrik can

use Kontak Player software. Kontakt Player software

is free. Therefore, we can omit the PC software cost

from the overall expenses. The main cost of building

this system is for the construction of the gamelan

instrument and the embedded controller system as the

midi controller. Each instrument has its own

mechanical interface and controller. Therefore, if we

need ten instruments in our gamelan set, we must

make ten set of hardware and ten set of midi

controller. Cost to build one set of one instrument

hardware interface and one midi controller is around

Rp. 400.000,00 including mallet and wiring system.

We can arrange one set of gamelan for example

consist of: 2 Sarons, 2 Demungs, 1 Peking, 1 Bonang

Penerus, 1 Bonang Barung, 1 Slentem, 1 set of Gongs

and Kempuls, 1 set Ketuk and Kenong. In total there

are 10 instruments, so the total cost is around Rp.

4.000.000,00. We assume that school has their own

PC and sound system already, so we exclude it from

our cost estimation. According to one source from the

Internet (SB Flash Art, 2019), the price of one set

fine gamelan made of iron is Rp. 125.845.000,00,

made of brass is Rp. 352.195.000,00, and the most

expensive made of bronze is Rp. 654.095.000,00.

CONCLUSIONS

The results showed that the development of the

electric gamelan or Gamelan Listrik has been

successfully conducted. The instrument input

response is quite fast with 13.5 ms latency time. It

Gamelan Listrik: A Low-cost Solution to Introduce Javanese Gamelan to the Young Generation

175

means the delay is almost un-noticeable. The

maximum input frequency is 6.7 Hz which is also fast

enough to handle basic gamelan practice hitting

speed. The volume level of the instrument can be

controlled by varying the striking force of the mallet.

It is easy to add instrument to the ensemble. Just by

connecting new instrument through the USB Midi

hub and set the midi channel for the new instrument.

Playing in solo also possible. The playing command

of all instruments in a single song can be pre-

programmed into independent microcontroller. Just

by managing the midi channel, we can set what

instrument should be muted and then we can play to

fill the muted channel using the gamelan hardware

instrument.

REFERENCES

Sumarsam, Introduction to Javanese Gamelan, Notes for

Music 451, Wesleyan: Wesleyan University, 1988.

H. Johnson, "Composing Asia in New Zealand: Gamelan

and Creativity," New Zealand Journal of Asian

Studies, vol. 10, pp. 54-84, 2008.

P. S. P. Wardhana, I. G. M. Darmawiguna and I. M. G.

Sunarya, "Pengembangan Aplikasi Instrumen

Gamelan Gong Kebyar Berbasis Android," Jurnal

Nasional Pendidikan Teknik Informatika (JANAPATI),

vol. 4, no. 2, 2015.

R. W. Resna, I. Yusniarsih and P. L. Yuliani, "Study On

Gamelan Degung As Music Therapy In An Active

Labor Phase On The First Stage Of Labor By Using

Pain Intensity Rating Scale," International Journal of

Advances in Science Engineering and Technology, vol.

5, no. 3, 2017.

S. Ismail, "Music and Music Intervention for Therapeutic

Purposes in Patients with Ventilator Support; Gamelan

Music Perspective," Media Nurse Journal of Nursing,

vol. 1, pp. 129-146, 2011.

M. Mendonça, "Gamelan in Prisons in England and

Scotland: Narratives of Transformation and the “Good

Vibrations” of Educational Rhetoric,"

Ethnomusicology, pp. 369-394, 2010.

A. D. Purbayekti, "Proses Pembentukan Citra Modern

Gamelan Sebagai produk budaya Melalui Komponen-

Komponen dalam Iklan Gamelan United, Thesis,"

Universitas Atmajaya Yogyakarta, Yogyakarta, 2011.

A. W. Kurniawan and A. M. Syarif, "Perancangan

Aplikasi Pembelajaran Orkestra Gamelan Secara

Mandiri Berbasis Computer Assisted Instruction,"

Techno.COM, vol. 12, no. 4, pp. 231-240, 2013.

Z. Wijaya, "Pengembangan Multimedia Pembelajaran

Interaktif Pokok Bahasan “Alat Musik Gamelan”

Untuk Pembelajaran Bahasa Jawa Sekolah Dasar Kelas

V, Skripsi," Program Studi Teknologi Pendidikan

Jurusan Kurikulum Dan Teknologi Pendidikan

Fakultas Ilmu Pendidikan, Universitas Negeri

Yogyakarta, Yogyakarta, 2015.

M. B. Hesananta, "Perancangan Alat Musik Virtual

Bonang (Gamelan Jawa) Berbasis Android

Menggunakan Sensor Ultrasonik Dan Arduino,

Skripsi," Program Studi S1 Teknologi Informasi

Fakultas Ilmu Komputer Dan Teknologi Informasi

Universitas Sumatera Utara, Medan, 2018.

P. A. Sumirat, "Aplikasi Alat Musik Gamelan Jawa Pada

Perangkat Android," Jurnal Emitor, vol. 14, no. 1.

A. O. Wiriadjaja, "Gamelan Sampul: Laptop Sleeve

Gamelan," in 13th International Conference on New

Interfaces for Musical Expression, NIME’13, Daejeon,

Korea, 2013.

"Native Instrument website," [Online]. Available:

https://www.native- instruments.com/en/products/

komplete/samplers/kontakt-6- player/kontakt-6-player-

vs.-kontakt-6/. [Accessed 3 February 2019].

"SB Flash Art," [Online]. Available: https://

sbflashart.com/blog/tag/jual-gamelan-jawa-komplit-

perunggu-super-termurah-di-jawa-timur/. [Accessed 4

February 2019].

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