Electro-mechanical setter

Comptons patented a form of combination action with a electro-mechanical memory; many are still functioning and are a testament to the ingenuity of this innovative organbuilder who even licenced their use to other makers.

The console is provided with a ‘setter’ piston which enables the organists to rapidly set chosen combinations as follows:

Compton Pistons
Compton Pistons

• Set the chosen registration on the department concerned
• Press and hold the setter piston
• Continuing to hold the setter piston, press the piston on which the chosen combination is desired to be set
• Release the piston, then release the setter piston.

To give a very simplified outline of what happens, the act of pressing the setter piston allows electrical contacts corresponding to each stopkey which is ‘on’ to latch into place on a conductive rail. There is a conductive rail for every thumb piston, so in fact the number of contacts is multiplied by the number of pistons. The conductive rail is moved by a solenoid coil when the thumb piston is operated; once the setter piston is released, the contacts stay latched in position on the conductive rail. When the thumb piston is subsequently pressed and the conductive rail moves, current flows through the contacts and energises the stopkeys ‘off’ or ‘on’. These systems normally had no facility to provide a neutral setting although individual stops could be neutralised by the organ builder.