The work holds the distinction of being the only full-fledged string quintet in Schubert's vast oeuvre. It also stands out for its somewhat unconventional instrumentation, employing two cellos instead of the customary two violas. Most other string quintets follow the example of Mozart and call for an ensemble consisting of the four standard instruments of the string quartet (two violins, viola, and cello), plus a second viola. Schubert, like Luigi Boccherini before him, decided to replace the second viola with an additional cello, thereby enhancing the richness of the quintet texture's lower register.
The work consists of four movements:
In common with other late works (eg. the Symphony in C major, D. 944, the Piano sonata in B-flat major, D. 960, etc.), the opening movement is broadly expansive, accounting for more than one-third of the total length of the piece. The second movement is in three part ABA (Ternery) form. The outer sections, in E Major, are of an otherworldly tranquility. The central section is intensely turbulent; it breaks in on the tranquility almost cruelly, in the unrelated key of F Minor. When the opening music returns, there is a running 32nd note passage in the second cello which seems to have been motivated by the turbulence that came before it. In the last three measures of the movement, Schubert somehow contrives to tie the entire movement together harmonically with a quick, brilliant modulation to the F minor of the middle section and an immediate return to E Major. The Scherzo is symphonic and large-scaled, with the open strings of the lower instruments exploited in an innovative manner to create a volume of sound which seems beyond the capabilities of five stringed instruments. The middle section, or trio of this movement is an unearthly slow march which seems to predict the sound world of Gustav Mahler. The last movement is an exuberant rondo with clear Hungarian influences.
While it was thought by earlier critics to lack the polish appropriate to a work of high-classical art music, it has grown steadily in reputation. Current consensus holds that the Quintet represents a high point in the entire chamber repertoire; the work is regarded as deeply sublime, with moments of unique transcendental beauty. It incorporates many unusual technical features, including the final two notes: the flat supertonic and the tonic, played forte in all parts.
The second movement's plaintive mood makes it popular as background music for pensive or nocturnal scenes in film. Examples include the 1989 Nocturne Indien, the 2001 film Conspiracy, and the 2003 film The Human Stain. Also Episode 21 from the Inspector Morse television series (Dead on Time) draws extensively from this string quintet, as do certain episodes in Desmond Morris' BBC series The Human Animal.
Schubert's string quintet was inspired by Mozart's third string quintet, written in the same key, as well as similar quintets by George Onslow. The instrumentation is reminiscent of Onslow, who used a double bass in some of his quintets. The opening theme of Schubert's work has retained many of the characteristics of the Mozart quintet's opening theme, such as decorative turns, irregular phrase lengths, and rising staccato arpeggios (the latter appear only in Schubert's recapitulation).
In turn, Schubert's work inspired Johannes Brahms in the writing of his Piano Quintet. The third movement of Brahms's quintet, written in C minor/major, ends in the same manner as Schubert's finale, with strong emphasis on the flat supertonic, D flat.