Minao Shibata left some works called ‘improvisation’. Among others, this piano solo piece, given the work number 20, was composed and played for the first time in 1957. Shibata mentioned this work is an easygoing short piece and the title means free improvisation of serialism.

How its harmony sounds, along with dynamics and string striking speed, decide the character of this piece. Shibata found that individual tone of sounds each pianist creates lays in a tone color of the chords. He said, the passage speed of hammer leaped up into the space in 4.8cm and the energy of the instantaneous string beating, both make the sound different each time. For example, the difference six chords (suppose that three keys are played in each hand) make can present the difference of the sound performed by each pianist.

The score for “Improvisation No. 1 for piano” was included in “the World Music Collection, Instrumental music section, Vol. 60”. This piece starts at Lento and changes its speed many times and end at molto Vivace.

This piece is characterized by various musical expression, for instance, staccatos like a whisper in ‘pp’ and lofty jumping staccatos and a single tenuto staccato, even though these are all the staccatos, it has so much of variety. We can enjoy the various tones in this piece, and if you pay attention to the treatment of the rest in a songful way, you will be able to perform this piece in a lively way.