Klung
an automated anklung

2000 -2006

This instrument is a computer controlled acoustical angklung designed and build in 2000. In 2006 it has undergone a major upgrade of the entire hardware. The anklungs themselves are made of hardened brass and tuned to a western scale covering two octaves. The instrument can be played by standard MIDI commands. It is mounted on a heavy duty trolley and can be taken on the road for street performances. However, it is not rain resistent and should be protected against moisture.

<Klung> played its very first automated scales on sunday the 18^th of june 2000.

On june 21th its builder wrote a tango for this instrument. This composition was called 'KlungelTango' and is scored for <Klung> in combination with a singer or a melodica. The computer program was written in <GMT> and is interactive. The piece can be performed on the street by a single performer. This tango was premiered on monday 4th of july, the melody performed by Karin Defleyt and the tango danced by the author with his partner, Moniek Darge. It was recorded for RTBF-television.

The instrument was made and designed to be a part of the <Slag-Werk> project realized for 'Web Strikes Back'at the occasion of the Tromp biannual, october 2000 in Eindhoven, the Netherlands.

A first composition that became a part the the <Web Strikes Back> project is called 'Klungels'. Both a version for the 'Klung' as a simulator version using real samples recorded from 'Klung' as well as a plain vanilla midi version is available as part for downloading from the Logos website. Work on this interactive software was also done by Kristof Lauwers. The musical range for this robot is:

Note that each note sounds in 3 octaves simultaneous. Sound sample of note 60 (C). (.wav format)

Midi implementation table:

Klung responds to messages and commands only on midi channel 4

The instrument uses following dedicated hardware:

1. two PIC (18F4620) controlled mosfet driver boards taking input from a midi port on a PC, with following schematic:

There are 20 anklung-notes in the intrument, each note always sounding in 3 octaves, as usual on the original indonesian instruments, made of bamboo. Our anklung however does not use bamboo but brass tubing and was rebuild from an old German instrument designed to be used in the circus. The original instrument was to be used by a musical clown and even had small electric lights fitted. (During our upgrade in 2006 we fitted lights again). This use explains why the tuning of the instrument conforms to A=440Hz and is tuned in equal temperament. The ambitus is C#- A(49 - 69). The angklungs are actioned by strong bidirectional solenoids. These are rated nominally 24V/ 1A delivering a force of 24 Newton. In order to get a higher range of striking velocities, we operate these solenoids at a little more than twice the rated voltage, limiting the duty cycle to 25%. At these voltage levels, one should never leave the coils under current. Doing this has no musical advantages nor uses and may only lead to an early death of the solenoids or the power supply. Since the rebuild in 2006 it became actually almost impossible for users to do this. The only potentially dangerous thing could be to send notes faster than the instrument can react to. In such a case the instrument would not sound a note but may still get very hot.

2. The 40 power mosfets we used for controlling these solenoids are Harris RFP10N12L (or the modern equivalent IRL640), since these switch on TTL levels and are capable of dissipating 60Watts. The current rating is 17A and their Uds limit is 200V. The rather high gate capacitance (1200pF) is not a real problem since switching speeds in this application are inherently pretty slow. For this reason we did not fit a resistor between gate and ground in the driver circuit. Note that when the power supply is switched on, all PIC outputs could go to a high state, thus sounding al notes at the same time. This is a detrimental condition of course. To avoid this, we modified Klung such that the instrument has to receive an explicit power on command (midi controller 66) from the connected PC before it will be fully powered on. In the 2006 implementation, the PIC's take care of all these technicalities, but still switching the instrument fast on and off using the power switch can be dangerous and should be avoided. The midi implementation is as follows:

- Note ON commands (144+channel, notebyte,velocity) on the selected channel for the notes 49 to 69 toggle the angklungs either forwards or backwards. The velocity controls the striking force and corresponds to the electrical pulse duration expressed in ms and divided by two.

- Note Aftertouch command can be used to set a periodic shaking frequency for the playing note. The command is 160 + channel, notebyte, period. The period is a value between 1 and 127 and is converted to 0.2 to 25.4Hz. (divide the midi byte by 5 to get the shaking frequency in Hz). Controller 69 can be used to switch this polyphonic aftertouch mode off..

- Note OFF command switch notes off ,also when aftertouch commands were sent. When aftertouch commands are not used, it is not strictly essential to send note off commands.

3. The power supply for this instrument is rated for 500Watts. The only reason for using two transformers had to do with the availability of off the shelve transformers in our regular electronic hardware retail store. The 5V required for the logic circuits is derived from a separate small 9V transformer. The relais works under command of midi controller 66 and is a heavy duty truck- type encapsulated relais rated for 80A. The resistor in series does get hot indeed...

Music:

Specific compositions for this instrument are written by Kristof Lauwers, Brent Wetters, Thomas Smetryns, Kris De Baerdemacker, Charlemagne Palestine, Sebastian Bradt and myself. We herewith invite any composer interested, to submit a piece for <Klung>. The midi implementation, for people not using <GMT> is as follows:

To shake the anklungs: notes 49 to 69, the shaking direction will alternate automatically. Note that note 68 (G#) is missing in the instrument. You should limit the shaking speed to lower than 12 beats a second. Velocity is implemented, so you can do crescendo's, accents etc... Obviously the instrument is intrinsically shaky in a very reliable way...

If you are using <GMT> under Power Basic, you can use all specific hardware control functions and procedures provided in our library. The low level functions can also be used by C programmers, since they are exported and reside in a standard DLL library. It is also possible to controll <Klung> using a microcontroller or even a simple Basic Stamp: the BS2 stamp just works nicely. In can output midi directly.

Available compositions and/or arrangements for <Klung>:

• 'KlungelTango' by Godfried-Willem Raes
• 'Klungels' by Godfried-Willem Raes
• 'StochKlung' by Kristof Lauwers
• "To Brent 2" by Thomas Smetryns
• Click here to hear this piece in MP3 format:
• "Trio Paradiso" (for Klung, Harma and Vibi) by Godfried-Willem Raes .
• "Paradiso" (for <Vibi>,<Klung>,<Harma>,<Piperola>,<Player Piano>,<Troms>
• "GestroMetals" (for <Belly>,<Klung>,<Vibi> and invisible instrument)
• "Grays for Klung" by Godfried-Willem Raes
• "Rolands Round" by Godfried-Willem Raes
• "Klungel Harm" by Godfried-Willem Raes

Concerts where <Klung> could be heard:

• Sunday 10th of september 2000, Kasteelpark Melle, Brusselsesteenweg (near Gent).
• Tuesday 17th of october 2000: Logos Tetrahedron: Try out concert
• Tuesday 24th to Sunday 29th of october 2000, Eindhoven, TU: <Web Strikes Back Project>,(Netherlands)
• Thursday august 2nd 2001, Ghent: Logos Tetrahedron
• Sunday september 9th 2001, Sint Truiden, Stadhuis (10u00-18u00)
• Thursday october 27-29 2001, Tourcoing, Le Grand Mix (France)
• Monday november 12th 2001, Amsterdam, Paradiso (Netherlands)
• Saturday december 1th,2001, Herne, Teutoburgia Halle (Germany)
• Tuesday december 4th, 2001, Ghent, Logos Tetrahedron
• March 27th, 2002, Ghent, Logos Tetrahedron (M&M ensemble)
• April 23th, 2002, Ghent, Logos Tetrahedron (M&M ensemble)
• July 20th,21th and 22nd, 2002, Ghent, Logos Tetrahedron (M&M ensemble)
• August 10th and 11th, 2002, Ghent, Paterholfeesten, Oudburg
• August 12th, 2002, Ghent, Logos Tetrahedron (M&M ensemble)
• November 28th, 2002, Enschede, Tart Symposium (M&M ensemble)
• December 19th, 2002, Ghent, Logos Tetrahedron (M&M ensemble)
• Februari 13th, 2003, Ghent, Logos Tetrahedron (M&M ensemble)
• March 13th, 2003, Ghent, Logos Tetrahedron (M&M ensemble)
• October 2003, Den Haag, Festival De Branding (M&M ensemble)
• January 2004, Den Haag, Korzo Festival (M&M ensemble)
• January 2004, Lille, Lille 2004 Robots (M&M ensemble)
• April 2004, Paris, France (M&M ensemble)
• March 2005, Leuven, Stuk (M&M ensemble)
• July 2005, Muenchen ,Germany (M&M ensemble)
• August 2005, Ruemlingen Festival ,Switserland (M&M ensemble)
• October 2005, Leuven, Transit Festival (M&M ensemble)
• December 2005, Ghent, Logos Tetrahedron (M&M ensemble)
• March 2006, Ghent, Logos Tetrahedron (M&M ensemble)
• November 2006, Koeln, Gimik, (M&M ensemble)
• November 2006, 's Hertogenbosch, Netherlands (M&M ensemble)
• July 2007 , Spiegeltent Gentse Feesten, Baudelopark (M&M ensemble)
• March 27th 2009: Gent Scheppende Stad: (Vooruit)

Collaborators on the construction and maintenance of <Klung>:

• Kurd Vandevelde
• Moniek Darge
• Xavier Verhelst
• Sebastian Bradt

Collaborators on the <Klung> software:

• Kristof Lauwers (GMT application coding)
• Johannes Taelman (PIC version 2006)

Dimensions and technical specifications:

• width: 1650 mm (with handle, 1750mm)
• height: 1600mm
• depth: 52 0mm
• weigth: 150kg
• power consumption: 512Watts (peak) / 230V AC. Normal average power taken up when playing: 75W. At rest: 20W.
• data input:. Since 2006 <Klung> is provided with a standard midi port.
• data output: 3 midi thru connectors are available.
• Insurance value: 13.500 Euro.

The <Klung> automat can be heard on the Logos Public Domain CD <Automaton> (LPD007)., as well as -in combination with many more automats in CD <M&M> (LPD008). It is also featured on LPD0014: <Robodies> (2005)

Last update: 2009-05-17