BALANCED SWELL PEDAL
At the commencement of the period of which we are treating (some fifty years ago) the Swell shutters of almost all organs were made to fall shut of their own weight, or by means of a spring. The organist might leave his Swell-box shut or, by means of a catch on the pedal, hitch it full open.
When, however, he wanted the shutters in any intermediate position, he had to keep his foot on the pedal in order to prevent its closing.
The introduction of the balanced Swell pedal (Walcker, 1863) has greatly increased the tonal resources of the organ. It is used almost universally in this country, but strangely enough the country in which the Swell-box was invented (England, 1712) lags behind, and even to-day largely adheres to the old forms of spring pedal.
A further and great step in advance appears in recent organs built by the Hope-Jones Organ Company. The position of the swell shutters is brought under the control of the organist's fingers as well as his feet. Each balanced swell pedal is provided with an indicator key fixed on the under side of the ledge of the music desk, where it is most conspicuous to the eye of the performer. As the swell pedal is opened by the organist's foot, the indicator key travels in a downward direction to the extent of perhaps one inch and a quarter. As the organist closes his pedal, the indicator key again moves upward into its normal position. By means of this visible indicator key the organist is always aware of the position of the swell shutters. Through electric mechanism the indicator key is so connected with the swell pedal that the slightest urging of the key either upward or downward by the finger will shift the swell pedal and cause it to close or open as may be desired and to the desired extent. When an organ possesses four or five swell boxes, and when these swell boxes (as in the case of Hope-Jones' organs) modify the tone by many hundred per cent., it becomes highly important that the organist shall at all times have complete and instant control of the swell shutters and shall be conscious of their position without having to look below the keyboards. Hope-Jones also provides what he calls a general swell pedal. To this general swell pedal (and its corresponding indicator key) any or all of the other swell pedals may be coupled at will.
Hope-Jones has also recently invented a means of controlling the swell shutters from the manual keys to a sufficient extent to produce certain sforzando effects.
When this contrivance is brought into use upon any manual and when no keys upon that manual are being played, the swell shutters assume a position slightly more open than normal in relation to the position of the swell pedal. Directly any key upon the manual in question is depressed, the swell shutters again resume their normal position in relation to the swell pedal. This results in a certain emphasis or attack at the commencement of each phrase or note that is akin to the effect obtained from many of the instruments of the orchestra.
These contrivances are applicable only to such organs as have the balanced swell pedal.