Abstract: Implementation including an outputter (11) following a control to output a signal, a microphone (10) for acquisition of sound from inside a ball (1a), a determiner (121) working in accordance with a level of sound acquired through the microphone (10) to determine a state of the ball (1a), and a control processor (122) working in accordance with a result of determination at the determiner (121) to generate a signal to output through the outputter (11).