The glissando machine can be relentless and sound very loud, almost more than 100 dB. That is dangerous to the ears, so it is better not listen for too long. But this loudness seems worse than it is, because it prickles uncomfortably in your ears. In the Glissando-Machine a heavy ball affects balance on the highest point of this bellow like rolling out on a lid. That lid opens and wind escapes so that the bellow collapses. Below the lid closes again and as a result the ball rolls back. Then the game starts all over again. Wind blows from the fan to the bellow and flutes. The bellow is filled up by wind pressure and pushes plugs into the flutes and the flute tones slowly rise in tone. In the other set the bellow pulls the plugs out from the flutes, resulting in descending glissandi sounds. The sound waves from all the flutes move through the space. Where those waves meet, they 'slosh' and those sloshes form together new wave patterns in the space. When the flutes differ sufficiently in pitch, the crashing of the drifting waves will rapidly create new forms: the alternating tones. These are fundamentally different in character than the ordinary tones, because they do not come from the flutes, but they arise everywhere in the space where those flutes sound. They arise therefore also in the ears of the public, and in this way seem threatening. Referee whistles work exactly this way. Six on and the six descending tones in the Glissando-Machine create a multitude of changes in the alternating tones, which all lie in everyone's ears. This creates that uncomfortable prickling feeling. This sort of automated machine could replace a musician and works in a way in which imitation by a performer is not easy. Moreover this sort of automated machine also has visual potential, it is a 'breathing object'; it is as if the work was alive. In 2006, two new Glissando-Machines were built; one goes up first, the other descends. They vary in speed and loudness, and sound rather charming, clearer, more balanced. But they still shriek, whimper, wail and whine.
The loud glissandi in this work arise by plastic tongues which are found on 'saxophone mouthpieces'. Such a 'mouthpiece' has been carefully formed into a curve, and as a result the reeds will tremble faster with increasing wind pressure. In this way such a flexible tongue movement is directly related to the wind pressure and the pitches glide easily. When several tongues are connected to one wind system, they have the inclination to react according to 'the law of the lowest resistance'. The tongues then trill in simplified proportions: the tones tune themselves in fifths or octaves. At a maximum wind pressure they produce an overwhelming sound mass, which is still reinforced by the sound beakers' As soon as the wind machine stops, the wind pressure on the flutes decreases gradually and everything relaxes. And then it becomes interesting, because a downward glissando is audible in those fifths and octaves.