Musical instruments

A pipe organ comprising a pipe sounding section having a rank of pipes for sounding musical notes, a note playing section having a plurality of playing keys allocated to individual notes and operable by a player of the organ, and a plurality of stops operable by the player of the organ for selecting desired correlations between keys played and pipes to be sounded, one of said stops selecting a given basic pitch relationship desired between the keyboard and the pipes, others of said stops selecting other pitch relationships desired between the keyboard and the pipes, said organ comprising time-division multiplex means for cyclically electrically sensing the operative conditions of the stops and keys and providing a multiplex signal representative of the operative condition of the organ at any time, means for transmitting the signal to the pipe sounding section of the organ, store means allocated to the individual stops, means for operating the store means from said signal to cause said store means to store sensed operative conditions of the stops, means for modifying the signal, said modifying means being means which are operable during each time-division multiplex stop that a key operative condition is being sensed and which modify the signal a number of times equal to the number of said pitch relationships whereby said modified signal successively represents the address of a pipe having said basic pitch relationship to the playing key being sensed, and the addresses of pipes having said other pitch relationships to the playing key being sensed, means for de-multiplexing the modified signal and means for controlling individual pipes in response to the signals from the de-multiplexing means, in accordance with the sensed operative conditions of the keys, there being gate means for each said desired pitch relationship, each said gate means having a plurality of inputs, there being means activating one said input in accordance with the playing key being sensed having been depressed, means activating another of said inputs from the store means allocated to a stop selecting and pitch relationship to which said gate means is allocated, means activating another of said inputs during the time period when the modifying means is effecting a modification of said signal appropriate to the pitch relationship to which said gate means is allocated, each said gate means having an output for enabling operation of said pipes by said pipe controlling means when all inputs of a given gate means are simultaneously activated.