Sound conversion device

A sound conversion device for converting an operation sound generated when a target equipment operates, comprising:

• a sound acquisition circuit configured to acquire the operation sound including abnormal sound as a sound pressure time signal that is a signal indicating a change in sound pressure intensity over time;
• a signal conversion circuit configured to
• convert a signal corresponding to the sound pressure time signal into a frequency characteristic indicating an intensity of sound pressure for each frequency including a human inaudible frequency band,
• obtain audible signal in which the frequency of an abnormal sound signal indicating the intensity of the sound pressure of the abnormal sound in the inaudible frequency band is changed to a human audible frequency band in the signal corresponding to the frequency characteristic, and
• output the audible signal as an audible sound signal that is a signal indicating a change in sound pressure intensity over time;
• and
• a speaker configured to generate sound based on the audible sound signal, wherein
• in an increase adjustment to increase the intensity of sound pressure at a frequency included in the abnormal sound signal and a decrease adjustment to decrease the intensity of sound pressure at a frequency different from the frequency included in the abnormal sound signal, the signal conversion circuit performs at least the increase adjustment to emphasize the intensity of the abnormal sound signal to obtain the frequency characteristic, and obtains the audible signal based on the frequency characteristic in which the intensity of the abnormal sound signal is emphasized.

A sound conversion device for converting an operation sound generated when a target equipment operates, comprising:

• a computer including a processor and a memory that stores instructions configured to, when executed by the processor, cause the processor to
• acquire the operation sound including abnormal sound as a sound pressure time signal that is a signal indicating a change in sound pressure intensity over time;
• convert a signal corresponding to the sound pressure time signal into a frequency characteristic indicating an intensity of sound pressure for each frequency including a human inaudible frequency band,
• obtain audible signal in which the frequency of an abnormal sound signal indicating the intensity of the sound pressure of the abnormal sound in the inaudible frequency band is changed to a human audible frequency band in the signal corresponding to the frequency characteristic, and
• output the audible signal as an audible sound signal that is a signal indicating a change in sound pressure intensity over time;
• and
• a speaker configured to generate sound based on the audible sound signal, wherein
• when the frequency of the abnormal sound signal straddles a frequency band having a predetermined bandwidth,
• the computer causes the processor to
• obtain the audible signal such that at least a part of the frequency of the abnormal sound signal is included in a high sensitivity band, which is a frequency band to which human hearing is more sensitive compared to other frequencies in the human audible frequency band, and
• remove a sound pressure signal in a frequency band higher than a predetermined frequency in a frequency band higher than the high sensitivity band in the audible signal.