Abstract: An automatic performance device includes: a pattern storage part, storing a plurality of performance patterns; a performing part, performing a performance based on the performance pattern stored in the pattern storage part; an input part, inputting performance information from an input device; a rhythm detection part, detecting a rhythm from the performance information inputted by the input part; an acquisition part, acquiring from among the plurality of performance patterns stored in the pattern storage part the performance pattern corresponding to the rhythm detected by the rhythm detection part; and a switching part, switching the performance pattern being performed by the performing part to the performance pattern acquired by the acquisition part.

Abstract: Musical sound signals in at least one frequency band in a low band range are enhanced by a low-pitched sound enhancement processing device. Musical sound signals greater than a predetermined level are compressed by a compression device, such that the level in a low band range would not become excessively large, while musical sound signals with a lower level are enhanced by an enhancement device to be outputted with sufficient sound pressure. Also, the input/output level ratio is determined based on the level of inputted musical sound signals, to prevent the output level from becoming smaller than the input level.