A timer may be for timing a current time period corresponding to an amount of time since a previous operation of an operator. Circuitry may be for processing data to carry out a performance based on a set tempo. The circuitry may be configured to change a position of the performance to a specified position of the performance in a case where the operator is operated and the current time period equals or exceeds a specified time period. The circuitry may be configured to change the tempo based on the current time period in a case where the operator is operated and the current time period is less than the specified time period.