To provide a sound effect parameter determining method, a sound effect detecting device, and a sound effect imparting device and a program that can easily simulate characteristics of nonlinear equipment since when a sound signal is recorded and reproduced by an analog type tape recorder, a sound is distorted because of characteristics of a magnetic head etc., and electronic addition of nonlinear distortion effect is possibly desirable.

Provided is the constitution of a sound effect detecting device which has a signal applying process of applying a reference signal to an object of measurement to convert a musical sound signal, a signal input process of inputting a nonlinearly converted measurement signal of the reference signal from the object of measurement, and an effect parameter calculating process of calculating an effect parameter for simulating the object of measurement according to the relation between the measurement signal and reference signal; and the effect parameter found through the effect parameter calculating process is used to impart nonlinear effect to the musical sound signal.