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by Richard Merewether
Copyright© 1978 Richard Merewether
At the mouthpiece-end, the horn commences with some 52 cm of tapered tube there ensues then (of necessity in valved horns, but of acoustical advantage anyway) a considerable length of non-tapered (i.e. cylindrical) tube wherein lies the valve-section. The taper then resumes for the final part (135 cm or more) to end in the widely-flaring bell.In XIXth-century horns the tube-diameter of the central cylindrical section was generally 11 mm or a little more, but in present-day instruments this has increased on average to 12 mm . The earlier type of instrument is not now in general use, and is only mentioned here because it did survive (in France, Belgium and England) until the middle of the XXth century; indeed in Vienna a variant of it is still played. Many of todays players received their initial training on the narrower horns, and this is revealed in their approach to the modern instruments which have now superseded those; more will appear on this subject later, under 'Holding the Instrument'.
Modern horns are conveniently classifiable into Medium, Large and Extra Large Bore, but it must be made clear that this does NOT denote the use of a wider-calibre middle or cylindrical section of the instrument. The difference lies in their tapered parts-mainly in the greater or lesser degree of flaring-out of the tube to give medium, wide or extra-wide bell-throat. The diameter at the rim however is usually standard at about 31 cm, though small variations in mouthpipe-taper are to be found as being more suitable for the different bell-throat sizes.
It should be stated that the notes of a medium-bore horn do not so easily wander in pitch as do those of larger-bored instruments; the former also more readily gives a well-centred, 'traditional' sound with less conscious study on the player's part. A beginner is not equipped to take care of numerous factors at once, and should have every available assistance in acquiring a good concept of tone without too many problems of intonation, so as to devote all effort to other pressing aspects of learning to play. As will be seen, most idiosyncrasies of larger-bored horns are catered-for in the careful observance of good right-hand technique, and when later able to form experienced judgments a player is well-advised to find out if a horn of different bore might suit his particular mode of production. Many do this successfully, and then without difficulty (even perhaps after some years) revert once more to a size smaller.
The student is thus well-counseled to choose as a first instrument one of not too large bore, and take particular pains to acquire as a sub-conscious habit the best possible right-hand position as discussed below; then it will be comparatively easy later to move about among horns of different bore and model, including Descant-horns.
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