Music signals are not solely characterized because of other mixed audio signals. Mixed audio signals contain music signals mixed with speech signals, voice and even background noise.Thus, mixed signals need to classify separately. Researchers have develope d many algorithms to solve this problem keeping in mind with their characteristic features of music signals: by timbre, harmony, pitch, loudness etc. The algorithm ICA (Independent c omponent analysis) uses basis of Blind source separation, HSS(Harmonic str ucture stability), "SOSM" APPROACH ( Second Order Statistical Measures Approach) , Sinusoidal Parameters based audio classification using FDMSM etc. are some of the mixed signal classification algorithms. This paper highlights all these existing methods and the ir experimental results.