Cadenzie e Duo-sonata

Kugel’s Cadenzie e Duo-sonata (Italian for “Cadenzas and Duo Sonata”) is a monumental work for viola and piano, completed in 2006. Lasting approximately 50 minutes​, it stands as one of the most ambitious concert pieces written for viola in recent decades. The concept of the piece is unique: it consists of a series of virtuosic cadenzas for several of the greatest viola concertos, integrated into the framework of a duo-sonata​.

In essence, Kugel fashioned new standalone cadenzas for famous viola concertos (by composers such as Bartók, William Walton, and others) and then connected them with piano accompaniment sections, creating a continuous work that can be performed as a sonata in its own right. The composer himself described it as “cadences for the greatest viola concertos: a must for each violist!”, underlining its dual role as a pedagogical compendium and a concert piece.

Cadenzie e Duo-sonata does not follow a traditional sonata form with defined movements; instead, it is structured as a sequence of cadenza-like chapters, each highlighting a particular style or theme associated with a major concerto. For example, one section might serve as a fantasy cadenza on Bartók’s Viola Concerto – featuring folk motifs and impassioned modernist flourishes – while another could be a cadenza for Walton’s Viola Concerto, exhibiting late-Romantic lyricism and bravura scale runs. Between these solo episodes, the piano enters, not merely as accompaniment but as a partner that sometimes introduces themes or connects one cadenza to the next. The term “Duo-sonata” implies that the piano and viola also engage in true duo interplay at times (unlike a typical concerto cadenza which is unaccompanied). Thus, after a lengthy solo cadenza, the piano might join for a development section or lead into the next concerto’s theme. The work likely opens with an introductory segment for both instruments, then cycles through multiple cadenzas (perhaps 4 or 5 major ones) before concluding with a finale where viola and piano share the spotlight. Throughout, Kugel showcases myriad styles: from Classical era flourishes (if he touches on concertos by Stamitz or Hoffmeister) to 20th-century idioms (Bartókian rhythms, Hindemith-like polyphony, etc.). The piano writing is demanding as well – at times providing orchestral-scale support (thundering chords, sweeping arpeggios) to give the feel of a full concerto accompaniment, and at other times engaging in chamber music dialogue with the viola.

Kugel wrote Cadenzie e Duo-sonata in his mature years as a performer-teacher, and it reflects his deep knowledge of the viola’s concerto literature. Traditionally, performers have written their own cadenzas for classical concertos (like those by Mozart or Stamitz), and 20th-century concertos sometimes include written-out cadenzas (Penderecki, Schnittke) or none at all (Bartók’s was left incomplete at his death). Kugel took this idea further by composing a comprehensive set of cadenzas as a single work – effectively distilling the essence of each great concerto into a solo showcase. This piece can serve violists in two ways: pedagogically, they can extract individual cadenzas to use in actual concerto performances or competitions (to replace or augment existing cadenzas), and artistically, they can perform the entire Duo-sonata on stage to demonstrate their command of multiple styles. In interviews, Kugel has emphasized the importance of virtuoso repertoire for viola; Cadenzie e Duo-sonata is an outgrowth of that philosophy, providing challenging material that pushes violists to the limit. Given its length and scope, one could imagine Kugel conceived it as a summation of viola technique – almost a “grand tour” of the instrument’s capabilities through the lens of famous concertos.

Cadenzie e Duo-sonata is a niche work, admired mainly by viola specialists for its ambitious scope. It is not frequently performed in full (its length makes programming difficult), but parts of it have entered practical use. For instance, violists have adopted Kugel’s cadenzas from this work when performing concertos – his cadenzas for the Bartók concerto or other classics are sometimes quoted for their inventiveness. Within Kugel’s oeuvre, this composition is recognized as a testament to his devotion to the viola: one reviewer dubbed it “a must for each violist” in terms of study and repertoire​.

Future generations of violists may rediscover Cadenzie e Duo-sonata as a valuable repository of stylistic cadenzas and a singular work that bridges the gap between concerto and sonata form.⁴