Patent ID: 8340963

Claim:
An echo suppressing system, comprising: a sound output device for outputting sound based on a sound signal, wherein the passing section comprises a plurality of bandpass filters including a passing section for allowing passage of a component of a different frequency band for each of a plurality of sound signals, and a plurality of sound output sections, each of which outputs sound based on each of the plurality of sound signals passed through the passing section; a summer for summing the plurality of sound signals passed through the passing section to generate a reference sound signal; a sound input device for converting input sound into a sound signal; and an echo suppressor for suppressing echo based on the sound output by the sound output device from the sound input to the sound input device, including an input section to which a sound signal is input from the sound input device as an observation sound signal, and a correction section for correcting the observation sound signal so as to suppress echo included in the observation sound signal based on the observation sound signal and the reference sound signal, wherein the sound output device further includes a comparison section for comparing amplitude of a plurality of sound signals with one another for each frequency band to determine whether or not a value indicating a comparison result obtained by comparing the amplitude of one sound signal having a maximum amplitude with the amplitude of all the other sound signals is equal to or larger than a given value, the passing section allows passage of only the one sound signal for a frequency band determined to have a value equal to or larger than a given value by the comparison section, and the passing section derives a filter coefficient for each of the bandpass filters based on the comparison and changes the setting of the filter coefficient, when the comparison yields a sound signal equal to or larger than a given value, otherwise the passing section cancels the change of setting of the filter coefficient for each of the frequency bands when the comparison yields a sound signal equal less than a given value.