Facility: tetrahedron studio laboratory workshop archive shop documentation center

Logos Instrument Building Workshop



PVC instrument commissioned by Musica vzw

  • P: Polyphonic / Polyfoon / Projekt / Plastiek / Plastisch
  • V: Versatile, Variable, Verplaatsbaar
  • C: Contraption , Concertinstallatie/ Concertinstrument / Concertant


The idea is to design and build a modular yet consistent instrument using PVC material that could be played by many children in togetherness. The instrument should be transportable in a small van and mounting complexity should be low and take up a minimum of time. Sturdiness is essential as well as safety.

  • - 24 drumpipes / klopbuizen (tunable to many systems) Two modules, each one and a half octave.
  • - 2 Intonarumori (friction drums derived from noise makers as build by Luigi Russolo)
  • - 4 Kalliopes (derived from the design of 19th century steam whistles)
  • - 2 Singing Bicycles (an invention by Godfried-Willem Raes) adapted to use on modified home trainers
  • - 2 jumping rods (threaded rods mounted on a membrane, on which rings can rotate by gravity)
  • - 1 large friction drum (derived from instruments such as the quica, rommelpot, Waldteufel, Loewengebruell etc...)
  • - Whispers (Cavity resonators)
  • - Log drums

Realisation / Realisatie:

1.- Twee modules met elk 12 klopbuizen voorzien van opzetstukken waarmee de tonen kunnen worden gekozen. Bij elke module hoort een houder voor de ping pong paletten voorzien van een speciale laag zacht neopreen.

2.- Twee Intonarumori instrumenten met membraan, spanmekanisme en door een zwengel bediend strijkwiel.

3.- Een module met vier kalliopes voorzien van vier balgen en verbonden met witte flexibele PVC buizen. De module is in hoogte verstelbaar.

4.- Twee home-trainer zingende fietsen, elk met twee resonantiebuizen in PVC

5.- Twee draadstang modules met membraan ringschrijven en omkeermekaniek.


Earlier projects and compositions by Godfried-Willem Raes using PVC pipes:


  • Mattias Parent (PVC research and construction)
  • Laura Maes (project supervision)
  • Godfried-Willem Raes (metal and welding works, structural design)

Construction diary:

15.07.2014: Sketches for what mechanisms could be made using PVC pipes:

01-16.02.2015: Experiments carried out with different kinds of PVC. The idea to make PVC logdrums came out to be unworkable. So this design was cancelled from the list of possibilities.

17-18.02.2015: Construction of drums using large diameter PVC pipes by Mattias Parent. Although this works very well, we did not preserve them in the final project by lack of originality. The drums may be modified to large lions roars later.

21.02.2015:Construction of an experimental giant whisper, using vinyl LP records

02.05.2015: Singing bicyle, with two tones mounted on a home trainer:
25.05.2015: Scale 1:1 technical drawing made for the construction of the intonarumori.
26.05.2015: Welded base and mechanics for the first intonarumori instrument, using 400 mm diameter thick PVC pipe: Here is a detail of the crank and the friction wheel: The legs are made from two lengths of 1 m 1/2" gaspipe, bend under 90 degrees using the Ridgid hydraulic pump and welded to the base 50x30x3 profile. The PVC pipe mounts on the stand with three M12 bolts.

27-28.05.2015: Further work on the string tending mechanism in nylon and definitive mounting of the crank. Definitive studbolt mounted for limitation of the range for the tending mechanism.

30.05.2015: A new load of PVC pipe cames flowing in...

02-04.05.2015: Construction of the bellows for the kalliopes

06-07.05.2015: Construction of the second intonarumori instrument.

10-15.06.2015: Cutting, drilling and TIG-welding works on the hexagonal holding structures for the tube resonators. Each module will hold 12 tubes, 90 mm in diameter. The diameter of the complete module will become 1100 mm. There are two such modules, so in total 24 tubes.

16.06.2014: Mounting of the PVC tubes in the structure. The first of these modules is ready and playable... Welding of the T-stands for the two jumping rods. (50x30x3 steel and 25x25x1.5) The distance holder rods between the stands still has to be welded in. We first have to know how to rotate the mechanism.

17.06.2015: Different kinds of neoprene and rubbers tested for the construction of the playing pallets.

18.06.2015: Two modules ready. All exchangeable pipe lengths sawn off and tuned. Design alternatives for the kalliopes drawn out and studied.

19.06.2015: Welding and final construction works on the second intonarumori instrument. This will be made from orange sewer pipe PVC,

20.06.2015: Sawing, precision drilling and welding of the steel holder for the four kalliopes. These will be mounted on a sturdy tripod such that the height can be adjusted. The kalliopes are mounted on the structure in a vertical position.

21.06.2015: Painting of the welded construction. Mounting of the kalliopes. Construction and adjustment of the mounting brackets. First tests with the bellows.

22.06.2015: Finalising the construction of the threaded rod instruments: clamping mechanism and welding of the studs connecting both T's pieces. The painting still has to be done. And here is a picture of both beat-tube/ drum-pipemodules together:

23.06.2015: Finishing of the second intonarumori instrument.

24.06.2015: Final painting of all modules. Construction of the beaters for the drum-tubes. Instrumental setup demonstration for Musica.

25.06.2015: Printing of the labels with the pitches for the pipes. Further construction of playing pallets. Design and construction of two holders for the ping-pong pallets.

26.06.2015: Transport of the project to Musica in Limburg. Setup and installation Laura Maes and Mattias Parent at Alden Biesen. Some issues to be remedied are: the bikes are too loud in comparisson to the other modules. The threaded rods are too gentle. The first issue can be solved by placing a series resistor in the wires to the speakers. The second one, to replace the ring with heavier ones and to exchange the membrane with styrofoam.

28.06.2015: Premiere of the project at AlbaNova organized by Musica at Alden Biesen.




Last updated: 2015-06-26