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by Richard Merewether
Copyright© 1978 Richard Merewether
When the Horn finally attained general use as 3 valved instrument, the key of F (about 3.75 metres from mouthpiece to bell) was chosen as most convenient, but very soon players began to adopt shorter tube-lengths (giving higher keys) for greater accuracy in high playing, and the Bb-horn (2.74 m) gained wide use with an adjustable 4th valve added to assist low notes.By the beginning of the XXth century Double Horns were developed comprising both these in one instrument, and it is this type whether in full double or in 'compensating' form) which is firmly recommended as a basic instrument rather than a single-horn. Both kinds of Double Horn fulfill the same role acoustically; the compensating system has the advantage of being lighter in weight, but depends rather more on the precision of its valve-work for efficient performance-although this is of course vital in all horns. Unfortunately, deficiency in this respect in cheaper instruments has unjustly led to a mistrust of the compensating principle, which is quite unwarranted as such valve-work would be equally ruinous in any model.
More recently, double and even triple horns have been developed including what are known as 'descant' horns, an octave higher than those mentioned above. These instruments are definitely not recommended except for those who have already mastered the full range with a conventional horn.
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