Page:EB1911 - Volume 21.djvu/598

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572
PIANOFORTE


the competition for power piano makers had been gradually increasing the weight of touch to be overcome by the finger, until, to obtain the faintest pianissimo from middle C, at the front edge of the key, from three to four ounces was a not uncommon weight. The Broadwood grand piano which Chopin used for his recitals in London and Manchester in 1848, an instrument that has never been repaired or altered, shows the resistance he required: the middle C sounds at two ounces and a half, and to that weight piano-makers have returned, regarding two ounces and three-quarters as a possible maximum. Owing to the greater substance of the hammers in the bass, the touch will

Fig. 34.-Broadwood Barless Grand. always be heavier in that department, and hghter in the treble from the lesser weight. In balancing the keys, allowance has to be made for the shorter leverage of the black keys. When the player touches the keys farther back the leverage is proportionately shortened and the weight increased, and there is also an ascending scale in the weight of the player's blow or pressure from pianissimo to fortissimo. The sum of the aggregate force expended by a pianist in a recital of an hour and a half's duration, if calculated, would be astonishing. The most important structural change in pianos in recent years has been the rejection of support given by metal bars or struts between the metal plate to which the strings are hitched and the wrest-plank wherein the tuning pins are inserted These bars formed part of William Allen's invention, brought form ard by Stodart in 1820, and were first employed for rigidity in place of compensation by the Paris Erards two years later, Broadwood in London introducing about that time the fixed metal plate. The patent No. 1231, for the barless or open-scale piano taken out in London in 1888 by H. I. Tschudi Broadwood, is remarkable for simplification of design as well as other qualities Ten years elapsed after the taking out of the patent before the first barless grand was heard in public (January 1898 at St James s Hall). The metal frame, bolted in the usual manner to the bottom framing, is of fine cast steel entirely free from any transverse bars or struts, being instead turned up round the edges to form a continuous Hange, which enables the frame to bear the increased modern tension while providing additional elasticity and equality of vibration power throughout the scaling. The absence of barring and bracing tends to subdue the metalhc quality of tone so often observable in pianofortes constructed with heavy iron frames, and the barless steel frame being so much more elastic than the latter, no loss in resonance is perceptible. The tone of the barless grand is of singular beauty and sonority and is even throughout the compass. The problem of resonance-with stringed keyboard instruments, the reinforcement or amplification of sound-has, from the days of the lute- and spinet-makers, been empirical. With lute guitar and viol or violin The Increase of in the instrument Res, ,, , mce the sound-box comes in, combining the distinct properties of string and enclosed air or wind. With the spinet, harpsichord and piano we have to do wood, to amplify the initial chiefly with the plate of elastic sound of the strings; and the old » plan of a thin plate of spruce, put in slightly convex and with an under-barring of wood for tension has absorbed the attention of piano-makers. The violin belly, with its bass bar and sound post, has relation to it; but the recent invention of the Stroh violin has 7 shown that the initial string vibrations may be passed through a bridge, be concentrated, and adequately transferred to an aluminium disk not much larger than half a crown. The piano, with its numerous strings, cannot be so reduced, but the reinforcement problem is open to another solution, tentative it is true, but a possible rival. The “ Gladiator ” soundboard is the invention of Albert Schulz, late director of the piano manufactory of Ritmuller and Sohne of Gottingen. Dr Moser's name has been associated with the inventor's in the English patent. In the “ Gladiator ” two slabs of wood, with grain of opposed direction to give the necessary tension, are glued together, and the whole system of belly bars is done away with. There is a thinning round the edge, to facilitate promptness of speech. As we are still feeling our way towards an accurate and comprehensive statement of resonance, this invention is one claiming scientific interest, as well as being of possible practical importance. To return to the touch. The desirability of what is called repetition- that the jack or sticker, which from the depression of the key delivers the blow that raises the hammer to the strings, should never be far away from the notch or nose which receives the impulse-is as much an object of consideration with piano makers now as it has been since Sebastian Erard began those experiments in 1808 which ended Repetition. 1 ", -1;i 4 74.2. /' Q E FIG. 35 -Cary's Repeating Action. I, the butt in which the hammer is glued. E, a spring attached to the butt by a link of s1lk cord passed through a wire guide. The object is that though the key may be st1ll pressed down, the hammer returns buf 21 short distance to ensure a quick response to the blow if repeated.