Waropen Coast drum New Guinea „The most important instrument is the drum (siwa), mainly imported from the Haarlem and Moor Islands, where the population possesses noticeable skill in wood-work.
At the dance the drums have to harmonise on two levels; for this purpose the drum-skins have to be
constantly adjusted over a low fire, whilst small pieces of resin have to be stuck on them.
Evidently, the Waropen are rather demanding as regards the sound of the drum, the degree of the tension of the skin and the manner of beating. To many drums they give a name of their own and even at a distance they recognise them by their sound.“
Excerpt from: DR.G.J.Held – The Papuas of the Waropen, p.355. The Hague Martinus Nijhoff 1957