A Dictionary of Music and Musicians/Soundpost

SOUND-POST (Fr. âme; It. anima; Ger. Stimmstock), a cylindrical pillar or peg used in stringed instruments. Structurally, it is correlative to the bridge: bridgeless instruments have no sound-post. It is moveable, and forms no part of the structure, but is introduced through the treble sound-hole, and stuck in, by means of a tool made for the purpose, when the fiddle is ready to be strung up, in such a way as to rest firmly on the back and to support the belly, a little behind the treble foot of the bridge. The name indicates its importance. The French and Italians call it the 'soul' (âme, anima), the Germans the 'voice' (stimme) of the fiddle. If the fiddle were strung up without a sound-post, not only would the belly be crushed in by the pressure of the strings, but it would be destitute of all tone. The function of the sound-post is to transmit to the back the vibrations which the strings excite in the bridge and belly. The instrument does not vibrate and speak as a whole until this transmission has taken place; and the more accurate the adjustment of the post, the more perfect the transmission, and the freer and fuller the tone. Thin bellies, and high models, require as a rule thick sound-posts, and vice versa. The sound-post should be made of dry resonant pine free from shakes and knots; fiddle-makers will take two or three pieces, of suitable shape, and test their comparative resonance by throwing them sharply on the bench. Its proper substance and length, and the exact distance at which it should stand behind the bridge, vary in different instruments, and are not easily determined. Old instruments, having very elastic bellies, admit of considerable uncertainty as to the proper length. The longer it is the greater is the tension, and the more shrill the tone: the closer its fibres, and the greater its thickness, the thicker the speech of the instrument: the nearer it stands to the bridge-foot, the more powerful becomes the vibration, and the harder the pull of the bow on the strings. When it is added, that its extremities must be carefully fitted to the inner surfaces between which it rests, that it should be stuck in mathematically at right angles to the axis of the fiddle, and that its grain should cross that of the belly at right angles, it becomes obvious that the making and fitting of this insignificant bit of wood are among the most difficult and important matters in the adjustment of the fiddle, and require an experienced eye and hand.^[1] If all this is not properly done, the player's ear is dissatisfied, and he has recourse to experimental changes of its position, to facilitate which a hole is sometimes drilled in the sound-post, and a piece of string permanently attached to it, so that it may be shifted about at will. This practice should never be indulged in. The soundpost has only one proper position, and once placed there, and allowed to get well into its bearings, the fiddle will yield its proper tone. Otherwise the tone will necessarily be imperfect. The importance of the sound-post has led to many attempts to improve it. The writer has heard of metallic sound-posts, and has seen one made of glass, the effect of which was intolerable. More rational than such experiments as these have been certain variations in the sort of wood employed, and in the shape, the sound-post being made elliptical or polygonal, instead of cylindrical. None of these, however, have had any success, and the round piece of pine which has been in use from the earliest times will probably never become obsolete.—Shakspere, whose eye nothing escaped, gives the name of James Soundpost to one of the rebec-players in 'Romeo and Juliet.'

[ E. J. P. ]

1. Stoss, of Vienna, one of the best of violin-fitters, used to say that perfection of tone in violins would never be reached until some one invented an instrument by which the sound-post could be gradually lengthened and shortened in the fiddle itself, as the wick of a lamp is raised and lowered in order to arrive at the proper incandescence. This, of course, is physically impossible: but the remark hints at the true solution of the difficulty.