explanation the operation of counter 82 will be discussed at this point while the generation of the three controlled signals will be discussed in reference to fig2 hereinafter a first input 49 to counter 82 consists of a logic signal indicating whether the arpeggio is to be up or down and is connected to both the up and down control terminal labeled u d in fig3 and the input data c terminal labeled c in fig3 when an up arpeggio is required the logic level on input 49 will be at logic 1 thus providing a logic 1 at the u d terminal and the data c terminal when the arpeggio is initiated a pulse is provided at input 88 to counter 82 which is connected to the load terminal of counter 82 when input 88 is pulsed the logic level at the three data input terminals a b and c are transferred to the three output terminals qa qb and qc of counter 82 the third input 90 to counter 82 is connected to the clocking terminal of counter 82 and consists of pulses which occur once after each of the three decoders 36 37 and 38 have been enabled thus keeping track of the number of times the set of decoders have been enabled the output of counter 82 consists of a three bit word indicating the octave of manual 8 in which multiplexer 40 is to be enabled counter 80 indicates which octave of manual 8 the multiplexer is currently scanning the outputs of counters 80 and 82 are compared by a group of exclusive or gates 92 and a nor gate 94 to provide a pulse at output terminal 96 whenever the outputs of counters 80 and 82 are equal output 96 will.