Basic envelope is produced for at least one tone on the basis of
performance information. In response to a free selection by a user, a
segment template including a characteristic variation curve is supplied,
and the characteristic variation curve of the segment template is placed
on a performance time axis. Then, the placed characteristic variation
curve and the basic envelope are combined together to produce a
synthesized envelope, and a tone is generated using the produced
synthesized envelope. A plurality of segment templates of different
lengths are prepared beforehand, which include phrase segment templates
corresponding to lengths of phrases, note segment templates corresponding
to substantial total lengths of tones, and tone-portion segment templates
corresponding to lengths of portions of tones. Two or more segment
templates of different lengths selected by the user are combined, as
necessary, so as to permit fine envelope control.
