An acoustic musical instrument a hollow body, neck, speaker, and digital audio device. A control circuit is coupled to the speaker and the digital audio device. The speaker is externally positioned on the hollow body. The digital audio player is externally positioned on the hollow body. The control circuit is communicatively coupled to a MIDI component, an electronic tuner, amplifier board, and an effects board. A plurality of light emitting diodes are positioned on the neck and coupled to the control circuit. The control circuit is configured to synchronicitously energize the LEDs with an audio file that is executed by the digital audio device. The control circuit is configured to synchronicitously energize the LEDs according to instructions received external to the acoustic musical instrument. The speaker is communicatively coupled to the amplifier board. The digital audio device captures sounds that are generated by the acoustic musical instrument.

The present invention provides a chordophone including a body configured to have a top plate, a bottom plate, and a side plate connected to the top plate and the bottom plate, which comprises: a cut-out plate formed by cutting the bottom plate, and configured to have a grille formed on a portion penetrated of the cut-out plate; a bracket formed in a shape corresponding to the cut-out plate and configured to have a base plate coupled to an inner side of the cut-out plate; and a speaker unit configured to have a speaker installed in the bracket, a control unit for controlling an output of the speaker, and a communication module for allowing a sound source output from the speaker to be received from an external user terminal, in which the grille is formed in a size and shape corresponding to a diameter of a side on which a sound of the speaker is output, and a through-hole is formed penetrated on the base plate at a corresponding position to the grille and with a corresponding shape to a shape of the sound output side of the speaker.

Provided is a device 1 including: a signal processing unit 40 that applies a rotary speaker effect corresponding to a rotation speed value to a sound signal and control a tone color of the sound signal; and a control unit 10 that gradually changes, in response to a change command of the rotation speed value, the rotation speed value from a first speed to a second speed higher than the first speed with a first change curve having a first delay, and gradually changes control of the tone color from a first characteristic to a second characteristic that is stronger in the high frequency range than the first characteristic with a second change curve having a second delay shorter than the first delay.

Provided is a device 1 including: a signal processing unit 40 that applies a rotary speaker effect corresponding to a rotation speed value to a sound signal and control a tone color of the sound signal; and a control unit 10 that gradually changes, in response to a change command of the rotation speed value, the rotation speed value from a first speed to a second speed higher than the first speed with a first change curve having a first delay, and gradually changes control of the tone color from a first characteristic to a second characteristic that is stronger in the high frequency range than the first characteristic with a second change curve having a second delay shorter than the first delay.

A speaker system includes one or more rotating speakers (or speakers with rotating reflectors) that are synchronized in absolute angular position to another rotating speaker or synchronized to audio effects to generated by a signal processing system driving a stationary or rotary speaker. Knowledge of absolute angular position in a multi-rotor speaker array or signal processing system allows for control of rotary position to accomplish acoustic effects otherwise not possible, such as matched-velocity profiles with differential phase control and motion profiles that are not based on simple rotation.

A speaker system includes one or more rotating speakers (or speakers with rotating reflectors) that are synchronized in absolute angular position to another rotating speaker or synchronized to audio effects to generated by a signal processing system driving a stationary or rotary speaker. Knowledge of absolute angular position in a multi-rotor speaker array or signal processing system allows for control of rotary position to accomplish acoustic effects otherwise not possible, such as matched-velocity profiles with differential phase control and motion profiles that are not based on simple rotation.

A keyboard device and a musical sound emission method are provided. A top lid is formed into a hollow structure including a lower plate and an upper plate facing the lower plate. Since vibrating bodies are fixed to an inner surface of the lower plate, the vibrating bodies can cause the lower plate to vibrate and thereby emit musical sound generated through the vibration from an outer surface side of the lower plate to the outside. On the other hand, the musical sound emitted from an inner surface side of the lower plate is blocked by the upper plate, and it is thus possible to curb mutual cancelation of musical sound in opposite phases emitted from each of the inner surface and the outer surface of the lower plate. Therefore, it is possible to efficiently emit musical sound to the surroundings of the top lid.

A sound signal conversion device includes a supplier. The supplier supplies a periodic change to an input sound signal and outputs the sound signal to which the periodic change is supplied. The supplier includes a phase determiner that determines a phase at which the periodic change supplied to the sound signal starts based on initial phase information when receiving a start instruction for starting supply of the periodic change to the sound signal.

A sound signal conversion device includes a supplier. The supplier supplies a periodic change to an input sound signal and outputs the sound signal to which the periodic change is supplied. The supplier includes a phase determiner that determines a phase at which the periodic change supplied to the sound signal starts based on initial phase information when receiving a start instruction for starting supply of the periodic change to the sound signal.

An audio stream is received from one or more of a plurality of microphones. A relationship between the audio stream and a user is detected. The detection is based on the audio stream from the plurality of microphones. The user wears a wearable device that includes the plurality of microphones. A direction of the audio stream is determined. The determination is based on the audio stream from the plurality of microphones. An alert to the user wearing the wearable device is output. The output is based on the direction of the audio stream. The output is also based on the relationship between the audio stream and the user.