Blending different string instruments together has always been a favorite activity among both composers and performers. The traditional string quartet (2 violins, viola and cello) has of course been the all-time favorite chamber music ensemble. From its early days beginning with Haydn, through most of the great composers of the 19^th and 20^th centuries, the quartet still reigns supreme. It's no wonder that this combination is such a favorite. For the composer it offers at least four voices over a 6-octave range combined with an expansive tonal palate and almost unlimited virtuosity available at a moments notice. Listeners can experience the ensemble in a wide variety of settings from a moderate size concert hall to a living room.

Less common but still very popular, especially among performers, is the duo. There have been hundreds of works created, many by major composers, utilizing various combinations of two string instruments, but combining the violin and the double bass, with each instrument treated equally, still remains an unusual adventure even in these opening years of the 21^st century. In the past, many reasons were given for this state of affairs; the most common being that the competence of bassists was not up to the same prowess of their smaller brethren. To any observer of the musical scene over the past 50 years it is obvious that this theory has been put to rest. While it is undeniably true that the classical music world reacts to any form of change ever so slowly and customarily with great suspicion, even those guardians of the status quo - whose mission is to protect us from any alien matter and other corrupting influences that might infect our art - have begun to see the light. Bassists are now being allowed into the neighborhood!

The Duo No. 2 for Violin and Double Bass was written in 2004 for violinist Larrie Howard and myself. Like my Duo No. 1, it is in four contrasting movements, calling for two stylistically versatile players.

The sections in the third movement calling for free improvisations, based first on a short tone row and then on a group of related phrases, can go in many directions. Rather than suggesting where I think that they should go, I'll instead encourage the bassist to be aware of the musical atmosphere that the work has inhabited and attempt to compliment its flavor. Try to resist the temptation to work out and play the same phrases (licks) each time. It's an improvisation after all! Use the violin part as a guide. Is it an accompaniment or should it be treated as an equal? All answers are correct – or wrong too.

The first performance of the Duo No. 2 took place on March 21, 2006 as part of the 2006 Hawaiian Contrabass Festival. The violinist was Darel Stark and the bassist was Frank Proto.

Frank Proto's Duo for Viola and Double Bass is the fourth in a series of recent duos for string instruments; the others are Sonata for Two Violas, Duo for Violin and Cello, and Duo No. 2 for Violin and Double Bass. The viola and double bass duo was completed in 2006 and written for former Cincinnati Symphony members Larrie Howard and Frank.

As you'd expect from a double bass player, the Duo shows the composer's intimate knowledge of his own instrument. Pairing it in an unusual combination with viola led Proto to exploit the dark, dusky timbres of the two instrument with imaginative interplay and all sorts of playing techniques and articulations that offer much more variety and fantasy than would seem possible for these two "dark horses" of the string family.

Some of the playing techniques--most notably the double bass's sliding pizzicatos (plucked notes)--are associated with jazz, but Proto's use of jazz is highly distilled, and for the most part he avoids conventional jazz figures and usages. One exception is the Duo's interludes of (optional) improvisation; here the relationship to jazz is stronger, though of course improvisation has a long history in so-called "classical" music also, going back to Bach and even before. Overall, Proto's vocabulary in his Duo is freely chromatic and often dissonant, with occasional more tonal-sounding points of reference, especially at certain cadences where the music seems to toy with the idea of sliding into a common chord--but then slips elusively away.

In the third movement Proto exploits the more shadowy nuances of his two strings with notable effect. The music is slow and sad, with an undercurrent of weariness and bittersweet nostalgia in the restrained counterpoint and incomplete cadences, one of which, reached by mirrored slow glissandos as both instruments slide in opposite directions, the viola up and the double bass down, appears three times as a point of rest.

The finale is the most virtuosic and the most openly jazzy movement of this very demanding Duo. After some opening flourishes, and a double bass improvisation, the big box takes up a cleverly intricate strumming-and-sliding triplet figure with a regular beat (marked "poco funk" in the score), over which the violist plays wildly scampering pyrotechnics that might be described by the oxymoron "composed improvisation." The double bass' insistent strumming figure returns, with interspersed slower episodes, several times, each time slightly differently and each time eliciting elaborate responses from the flighty viola, who finally sinks into exhaustion, now playing only long-sustained chords, at the work's surprisingly quiet conclusion.