The piano is often thought of as a primarily solo instrument. It is unique in this way. The piano has the largest pitch range of any instrument and the expressive capabilities of the human voice. It is very versatile – one of the few instruments that can provide harmony and melody at once. It is only surpassed in potential by a full symphony orchestra.
However, the harpsichord and clavichord, which preceded the piano, were originally used almost exclusively as accompaniments - usually for voice, strings or woodwinds. They had thin tones that provided rhythmic and harmonic constancy, basso continuo. Johann Bach (1685-1750) helped bring these instruments into independence by writing interesting counter-point works (e.g. the Inventions and Prelude and Fugues). These works were intended for teaching keyboard players harmonic and technical skills for improvisation of the continuo lines, which were written as letter and number symbols rather than notes (figured bass).
As the piano evolved, and with its increasing capabilities, composers began to write music that showed off or stretched the new technology. Chopin (1810-1849) is an example of a composer who wrote almost entirely for solo piano during this period. Piano music headed in two contrasting directions – continuo chamber-music parts and dynamic solos.
Chamber music is written for small groups of instruments, such as four strings. Piano parts evolved from simple harmonic support into balanced, melodious voices at the hands of such composers as Franz Schubert. Among Schuberts many works, there are two beautiful and interesting trios for piano, violin and clarinet (Opus 99 and Opus 100). In these trio Sonatas, each instrument plays an equal role.
Although the acoustic piano cannot be easily transported, due to electronic technologies making keyboard instruments responsive and somewhat authentic, there are now possibililtes of utilising the many interesting compositions that combine the piano with other instruments.
The piano can successfully stand alone, accompany or play ensemble, with four hands or other instruments.