47. Electronic musical apparatus for enabling a performer to control the production of at least first and second musical accompaniments during a musical performance, said apparatus comprising the combination of: first memory means for storing a first plurality of music signals defining at least in part the first musical accompaniment and a second plurality of music signals defining at least in part the second musical accompaniment and for storing with respect to at least portions of said first and second accompaniments information about the musical parameters of instrumentation pattern, duration, and pitch; accompaniment selection means operative during the performance for generatng a first selection signal in response to selection of the first musical accompaniment by the performer and for generating a second selection signal in response to selection of the second musical accompaniment by the performer; harmony selection means for enabling a performer to select one harmony from a plurality of different harmonies; second memory means for storing digital instructions for processing the music signals during the performance according to the one harmony; central processor means responsive to the selected selection signal and to selection of the one harmony for reading the music signals corresponding to the selected musical accompaniment from the first memory means and for processing the music signals corresponding to the selected musical accompaniment according to said instructions to form time-spaced digital parameter signals having changing digital values which define a segment of music including a plurality of pitched accompaniment notes arranged to express the selected musical accompaniment in the one harmony; and output means for converting the changing values of the parameter signals to sound, whereby a performer of limited skill or musical knowledge can play an orchestrated accompaniment to a variety of melodies.
47. Electronic musical apparatus for enabling a performer to control the production of at least first and second musical accompaniments during a musical performance, said apparatus comprising the combination of: first memory means for storing a first plurality of music signals defining at least in part the first musical accompaniment and a second plurality of music signals defining at least in part the second musical accompaniment and for storing with respect to at least portions of said first and second accompaniments information about the musical parameters of instrumentation pattern, duration, and pitch; accompaniment selection means operative during the performance for generatng a first selection signal in response to selection of the first musical accompaniment by the performer and for generating a second selection signal in response to selection of the second musical accompaniment by the performer; harmony selection means for enabling a performer to select one harmony from a plurality of different harmonies; second memory means for storing digital instructions for processing the music signals during the performance according to the one harmony; central processor means responsive to the selected selection signal and to selection of the one harmony for reading the music signals corresponding to the selected musical accompaniment from the first memory means and for processing the music signals corresponding to the selected musical accompaniment according to said instructions to form time-spaced digital parameter signals having changing digital values which define a segment of music including a plurality of pitched accompaniment notes arranged to express the selected musical accompaniment in the one harmony; and output means for converting the changing values of the parameter signals to sound, whereby a performer of limited skill or musical knowledge can play an orchestrated accompaniment to a variety of melodies. 52. Apparatus, as claimed in claim 47, and further comprising means responsive to a change in the selected musical accompaniment for changing at least one of the following musical parameters of the notes: (a) instrumentation pattern, (b) chord pattern, (c) melodic contour.