Often described as “the king of instruments”, the pipe organ has a number of stops which the organist uses to modify the sound. All pitched sounds are made up of harmonics and the footage values on the stops indicate the harmonic that the stop reinforces. “Organ stops” allows all the footages found on pipe organs on both the manuals and the pedals to be dialled up and it shows a very large number of stop names (over 500 for the manuals and nearly 300 for the pedals) that are in common use. One of these can be selected and it will be displayed on an on-screen drawstop along with its footage.
SOUNDS: Bottom C for the selected footage can be played by touching the stop knob (including a pedal 128 at 4 Hz (4 vibrations a second!) - YES over your iPhone/iTouch loudspeaker! Four snippets of organ music provided.
“Organ stops” also features a web-based interface describing the basics of how the pipe organ works with some illustrative images. In addition, there is a harmonic footage calculator which allows both the stop footage and the fundamental frequency for bottom C to be calculated for a selected harmonic between 1 and 48 of a chosen fundamental rank between 256’ and 1’.