Music data memory includes pieces of music within a group and other pieces of music outside the group. The next piece to be played is automatically determined by random table among pieces within the group. Favorite or newest piece is weighted to be more frequently played in the group. Piece in music data memory is automatically included into the group by random table. Newly downloaded piece into music data memory is included into the group by priority. Most frequently played piece is excluded from the group in place of newly included piece. Favorite or newest piece may be an exception of exclusion. Next piece is capable of being played in tempo similar to that of preceding piece by means of tempo-adjusted or piece replacement or repetition of the same piece for the purpose of continued baby cradling in synchronism with the same tempo of succeeding pieces.

Systems and methods capable of providing adaptive and responsive accompaniment to music with fixed chord progressions, such as jazz and pop, are provided. A system can include one or more sound-capturing devices, a signal analyzer to analyze captured sound signals, and an electronic sound-producing component that produces electronic sounds as an accompaniment.

Music data memory includes pieces of music within a group and other pieces of music outside the group. The next piece to be played is automatically determined by random table among pieces within the group. Favorite or newest piece is weighted to be more frequently played in the group. Piece in music data memory is automatically included into the group by random table. Newly downloaded piece into music data memory is included into the group by priority. Most frequently played piece is excluded from the group in place of newly included piece. Favorite or newest piece may be an exception of exclusion. Next piece is capable of being played in tempo similar to that of preceding piece by means of tempo-adjusted or piece replacement or repetition of the same piece for the purpose of continued baby cradling in synchronism with the same tempo of succeeding pieces.

Systems and methods capable of providing adaptive and responsive accompaniment to music with fixed chord progressions, such as jazz and pop, are provided. A system can include one or more sound-capturing devices, a signal analyzer to analyze captured sound signals, and an electronic sound-producing component that produces electronic sounds as an accompaniment.