Electronic musical instrument, power control device for electronic musical instrument, and power control method

A power control device for an electronic musical instrument, wherein the electronic musical instrument includes:

• a musical tone processing circuit that processes a musical tone signal according to an operation of a performance operant, an output jack configured to connect the musical tone signal to an amplifier, a phone jack configured to connect the musical tone signal to a phone, a USB jack to which a USB cable is connected, and a switch for turning power supply of the electronic musical instrument ON or OFF, and the power control device comprising:
• a control circuit, configured to determine whether power supply is necessary and select power supplied to the musical tone processing circuit from among first, second and third power based on:
• information indicating each power receiving state of the first power supplied via an AC adapter, the second power supplied via the USB cable, and the third power supplied from a battery,
• information indicating whether an output plug is inserted into the output jack, a phone plug is inserted into the phone jack, the USB cable is connected to the USB jack, and an ON or OFF operation of the switch is performed, and
• information indicating a power supply ON or OFF state of the electronic musical instrument.

A power control method for an electronic musical instrument, wherein the electronic musical instrument includes:

• a musical tone processing circuit that processes a musical tone signal according to an operation of a performance operant, an output jack used-to configured to connect the musical tone signal to an amplifier, a phone jack configured to connect the musical tone signal to a phone, a USB jack to which a USB cable is connected, and a switch for turning power supply of the electronic musical instrument ON or OFF, and the power control method comprising:
• allowing a power control device for the electronic musical instrument to determine whether power supply is necessary and select power supplied to the musical tone processing circuit from among first, second and third power based on:
• information indicating each power receiving state of the first power supplied via an AC adapter, the second power supplied via the USB cable, and the third power supplied from a battery,
• information indicating whether an output plug is inserted into the output jack, a phone plug is inserted into the phone jack, the USB cable is connected to the USB jack, and an ON or OFF operation of the switch is performed, and
• information indicating a power supply ON or OFF state of the electronic musical instrument.