This picture from the 1930's perfectly illustrates how my father liked to play for all sorts of audiences. It is included mainly to show the single F horn made by J.K.Gottfried which he used for most of his nine years with the Danish Radio Orchestra

My father has always considered that in order to develop a good sense of tone, one should start with the F horn, something that I was forced to "suffer" myself during my earliest acquaintances with the horn. Afterwards, one can advantageously change to the B flat horn while retaining the tone of the F horn. Wilhelm believed that tone is more a psychological than a physical reality and supports this idea by reference to the differing tone ideals in different countries. He meant that it is not merely the instrument that determines the tone, but rather what one wants to hear and not least, the tone that one has grown up with. Which is not to deny that different instruments and different mouthpieces can give some tonal variation.
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