A filter generator that generates the filter coefficients for a filter for performing a sound correction process on an audio signal by fast-Fourier-transforming, then filtering, and inverse-fast-Fourier-transforming the audio signal, the filter generator comprising: a weighting factor storage unit configured to store weighting factor information used to perform the sound correction process, for each of a plurality of bands obtained by dividing a frequency band of the audio signal; a gain coefficient storage unit configured to store preceding gain values of the divided bands set by a user before a preceding sound correction process and the filter coefficients of a preceding filter used in the preceding sound correction process; an input detection unit configured to detect a band selected by the user, of the divided bands as band information and to detect a new gain value newly set by the user for the selected band; a weighting factor extraction unit configured to extract weighting factor information of the band selected by the user from the weighting factor storage unit on the basis of the band information detected by the input detection unit; a gain difference calculation unit configured to calculate, as a gain difference, a difference between a preceding gain value of the band obtained from the band information, of the preceding gain values stored in the gain coefficient storage unit and the new gain value detected by the input detection unit; a correction gain generation unit configured to generate a correction gain of the band obtained from the band information by multiplying the weighting factor information extracted by the weighting factor extraction unit and the gain difference calculated by the gain difference calculation unit; and a filter coefficient calculation unit configured to generate the filter coefficients of a new filter by multiplying the filter coefficient of the band obtained from the band information, said filter coefficient being of the filter coefficients of the preceding filter stored in the gain coefficient storage unit, by the correction gain generated by the correction gain generation unit. a weighting factor storage unit configured to store weighting factor information used to perform the sound correction process, for each of a plurality of bands obtained by dividing a frequency band of the audio signal; a gain coefficient storage unit configured to store preceding gain values of the divided bands set by a user before a preceding sound correction process and the filter coefficients of a preceding filter used in the preceding sound correction process; an input detection unit configured to detect a band selected by the user, of the divided bands as band information and to detect a new gain value newly set by the user for the selected band; a weighting factor extraction unit configured to extract weighting factor information of the band selected by the user from the weighting factor storage unit on the basis of the band information detected by the input detection unit; a gain difference calculation unit configured to calculate, as a gain difference, a difference between a preceding gain value of the band obtained from the band information, of the preceding gain values stored in the gain coefficient storage unit and the new gain value detected by the input detection unit; a correction gain generation unit configured to generate a correction gain of the band obtained from the band information by multiplying the weighting factor information extracted by the weighting factor extraction unit and the gain difference calculated by the gain difference calculation unit; and a filter coefficient calculation unit configured to generate the filter coefficients of a new filter by multiplying the filter coefficient of the band obtained from the band information, said filter coefficient being of the filter coefficients of the preceding filter stored in the gain coefficient storage unit, by the correction gain generated by the correction gain generation unit.