Opus Two violin/piano duo


Opus Two has been internationally recognized for its “divine phrases, impelling rhythm, elastic ensemble and stunning sounds,” as well as its commitment to expanding the violin-piano duo repertoire. The award-winning duo, comprising violinist William Terwilliger and pianist Andrew Cooperstock, has been hailed for its “unanimity of style and spirit, exemplary balance and close rapport.”

Opus Two first came to international attention as winners of the United States Information Agency’s Artistic Ambassador Auditions in 1993 and has since performed across six continents, including major tours of Europe, Australia, South American, Asia, and Africa. Their US engagements include performances at Carnegie Hall, where they performed Haydn’s Double Concerto for Violin and Piano, Lincoln Center, Merkin Hall and a standing-room-only recital at New York’s Library for the Performing Arts. State Department associations have taken them to Japan, Korea, Russia, Ukraine, Germany, France, Switzerland, Peru, Ghana, and Australia, and they have also held multiple residencies in China. The duo has presented master classes worldwide at a number of prestigious institutions such as New York’s Juilliard School, Beijing’s Central Conservatory, and Kiev’s Gliera Conservatory.

Champions of American music, Terwilliger and Cooperstock have recently recorded Gershwin: Music for Violin and Piano, which features selections from Porgy and Bess, Gershwin’s original Short Story, Jascha Heifetz’s arrangements of An American in Paris and Three Piano Preludes, and newly commissioned arrangements by Broadway conductor/arranger Eric Stern of selections from Gershwin’s musical Girl Crazy and classic songs from the Gershwin Songbook. Singer-actress Ashley Brown, Broadway’s original Mary Poppins, joins them on Stern’s renditions of Love Walked In and Nice Work If You Can Get It. American Record Guide calls this an “excellent recording” in which “the performers throw themselves into this fresh look at Gershwin with enthusiasm and enjoyment.” The duo has created a multi-media program dedicated to this music and has presented it widely including a 20-concert tour of the Southeast and a highly praised performance at New York’s 54 Below.

Highlights of recent seasons include two twenty-city US tours across eleven states; performances with the Boulder Chamber Orchestra; and a European tour, which featured the duo in recital and as concerto soloists in Nice, Monaco, Bern and Geneva, and as invited guests of the US Ambassadors to Switzerland and the United Nations. The Strad praised the ensemble’s debut performance at London’s St. John’s, Smith Square as “beautifully drawn, brilliantly coloured and intense,” remarking that “violinist William Terwilliger played with supreme tenderness and finely judged control and was partnered with assurance and sensitivity by Andrew Cooperstock.” Opus Two’s festival appearances include performances at the Australian Festival of Chamber Music (Queensland), Piccolo Spoleto (South Carolina), Brevard Music Festival (North Carolina), Round

Top International Festival-Institute (Texas), Raritan River Music Festival (New Jersey), Rocky Ridge Music Center (Colorado), Vianden International Music Festival (Luxembourg), Hell Hot! New Music Festival (Hong Kong), Saarburg International Music Festival (Germany), and Classical Music Festival (Austria). The Boston Musical Intelligencer called Opus Two’s performance at Woodstock, New York’s venerable Maverick Concerts, the oldest such music festival in the country, “one of the most significant and worthwhile concerts of the season,” commenting that the program was “performed with virtuosity, musicianship and excellent balance.”

Opus Two’s discography features a critically acclaimed series of single-composer recordings of American music, including works by Aaron Copland, Leonard Bernstein, George Gershwin, Robert Starer, Paul Schoenfield, and Lowell Liebermann. The duo’s Naxos debut recording Leonard Bernstein: Violin Sonata; Piano Trio; New Transcriptions features the world premiere of Four Moments from Candide, by Eric Stern. Acclaimed as “an excellent recording, performed splendidly throughout,” the disc includes two additional Stern arrangements: “My House” from Peter Pan, and “Take Care of this House” from 1600 Pennsylvania Avenue, recorded with Tony-nominated actress-singer Marin Mazzie, as well as the duo’s own transcription, for violin and piano, of Bernstein’s Clarinet Sonata. A major grant from the American Music Center’s Aaron Copland Recording Fund made possible Opus Two’s world-premiere recording, Souvenirs: Music of Paul Schoenfield, which was hailed by American Record Guide as “accomplished, sophisticated, and filled with the sheer joy of music-making.” The duo has performed Aaron Copland’s complete works for violin and piano extensively across the United States and abroad, and their recording of this music features works never before recorded, including two early, unpublished preludes. The ensemble’s recording of chamber music of Lowell Liebermann features performances with cellist Andrés Díaz and the Ying Quartet, and was lauded as “splendid” by Strings magazine. John Fitz Rogers composed Sonata Lunaris for Opus Two, whose discography also includes two discs of works by Robert Starer, featuring the world premiere recordings of Duo for Violin and Piano, as well as Dispositions, written for the duo and clarinetist Martha MacDonald. In 2014 the duo commissioned Columbia composer Meira Warshauer to create Carolina Gallery, a musical triptych inspired by works by South Carolina artists.

In addition to their concerts as Opus Two, William Terwilliger and Andrew Cooperstock regularly join forces with Martha MacDonald as members of Trio Contraste. The trio has been honored with the Centennial Chamber Music Award for Outstanding Promotion of American Music from the National Federation of Music Clubs. Additionally, William Terwilliger and Andrew Cooperstock have collaborated together or individually with members of the Takács, Emerson, and Juilliard String Quartets, and the Dorian Wind Quintet, violinists Oleh Krysa and James Buswell, and cellists Lynn Harrell, Allison Eldredge, and Yehuda Hanani.

Opus Two’s radio and television credits include appearances on National Public Radio’s Performance Today, New York’s WQXR, Chicago’s WFMT, North Carolina’s WDAV, Colorado’s KVOD, the BBC, Radio France, Radio Latvia, and the Australian Broadcasting Corporation. Their South American tours have also included appearances on television in the Dominican Republic, Peru, and Bolivia.

Prizewinner in the National Federation of Music Clubs Young Artist Competition and the New Orleans International Competition, Andrew Cooperstock has performed in most of the fifty states as soloist and chamber musician. He has also given lectures and recitals at the Hochschule für Musik Hans Eisler in Berlin, Germany, the Academy of Music in Riga, Latvia, and the Central Conservatory in Beijing, China, among others. In honor of the Leonard Bernstein centenary, he has recorded a 2-CD set of the complete solo piano works of Bernstein for Bridge Records. Currently Cooperstock is Professor of Piano at the University of Colorado Boulder and a member of the artist-faculty at Saarburg International Music Festival in Germany. A graduate of the Juilliard School and the Peabody and Cincinnati Conservatories, he studied with Abbey Simon, Walter Hautzig, and David Bar-Illan, as well as with collaborative pianist Samuel Sanders. He is a Steinway artist.

William Terwilliger has performed with orchestras in the US, Europe, South America, and Asia, and he is concertmaster of the Long Bay Symphony. A graduate of the Eastman School of Music, he studied with Donald Weilerstein and Zvi Zeitlin, and as a member of the prize-winning Augustine String Quartet, he coached with the Cleveland, Tokyo, and Emerson Quartets. In 1993 he was invited by the US State Department to serve as a Cultural Specialist in Bolivia, and since that time, as a gifted and experienced teacher of students of all ages, he has given master classes throughout the US and in Europe, Asia, Latin America, Africa, and Australia. Currently Dr. Terwilliger is Professor of Violin at the University of South Carolina and artist-teacher at the Saarburg International Festival of Music.

Both musicians regularly present and serve as jurors for such organizations as the American String Teachers Association, the College Music Society, the National Federation of Music Clubs, and Music Teachers National Association. The list of awards to their credit includes grants from the American Music Center, Chamber Music America, the National Federation of Music Clubs, and the Arts International Fund, to name a few. William Terwilliger and Andrew Cooperstock have written articles for Strings, American String Teacher, and Keyboard Companion, among others. For more information please visit and follow Opus Two on Facebook. 

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William Terwilliger’s coloratura violin in “Glitter and be gay”, coming complete with bungee-jumping glissandos and gravity-don’t-bother-me note leaps, is infused with the spirit of Bernstein’s original vocal lines but sounds effortlessly violinistic...Terwilliger’s violin transcription of Bernstein’s 1942 Clarinet Sonata makes a connection I’d previously missed: the circular melodies and wandering-ear harmonies of the opening Grazioso hint at melodic contours Bernstein would explore a decade later in his Serenade (after Plato’s Symposium).

Terwilliger and Cooperstock perform splendidly throughout, and the recording is excellent. a worthy purchase for all fans of Bernstein and of mid-20th century American chamber music.
-Music Web International

The Clarinet Sonata is more effective on violin than I expected. In no small part, this is due to Terwilliger’s imaginative playing in which he imitates some of the clarinet’s tonal and coloristic effects by means of harmonics and special bowing techniques such as sul tasto, flautando, and at one point what sounds like sul ponticello.... and the disc can be recommended as a valuable addition to the composer’s chamber-music discography.

Bernstein’s many fans will want to have this album, especially since it offers so many rarities.
-American Record Guide

Recommended for Bernstein lovers.
-All Music

Persuasively performed in a Naxos release which also includes an effective violin transcription by William Terwilliger.
-BBC Music

The first-rate playing throughout by violinist William Terwilliger and pianist Andrew Cooperstock is virtuosic. I can't imagine any other duo playing these pieces any better. Highly recommended.

Terwilliger’s arrangement of Bernstein’s clarinet sonata is ironically more idiomatic for the violin than Bernstein’s own violin sonata... it is valuable to have this clarinet sonata in a transcription for violin... violinists deserve to have this excellent arrangement at their disposal.... Terwilliger and Cooperstock form a terrific duo with Opus 2; their program was equally engaging.
-New York Concert Review

I loved every minute of this fine release. It’s accomplished, sophisticated, and filled with the sheer joy of music-making. [Souvenirs: Music of Paul Schoenfield]
-American Record Guide

Only a great performance can convince a listener that a new piece is worth hearing. You did it.
-Paul Schoenfield

It would be hard to imagine finer performances of these works. [Aaron Copland: The Complete Works for Violin and Piano]
-American Record Guide
The playing is splendid. Opus Two is widely acclaimed for its tone, style, and polish.
-Strings Magazine

Their ensemble bears witness to their long collaboration in its unanimity of style and spirit, its exemplary balance and close rapport. Technically, they have complete command of their instruments. Terwilliger’s tone is remarkably pure, resonant, even and full, with a lovely radiance in the high register... Cooperstock’s control of touch and dynamics enables him to give substance to Copland’s often very sparse writing, to blend or contrast with the violin sound... [Re: Opus Two’s Copland recording for Azica Records] the playing is splendid, the sound excellent.
-Edith Eisler

An excellent duo. They clearly have a strong affinity and understanding for this music; they have performed it widely and have made an excellent recording on Azica Records. Their instrumental command, ensemble, and balance are admirable.
-Strings Magazine

Violinist William Terwilliger played with supreme tenderness and finely judged control and was partnered with assurance and sensitivity by Andrew Cooperstock. Two early preludes, full of abject Romanticism, were beautifully drawn, while the demanding 1943 Sonata was brilliantly coloured and intense. The late Duo was equally fine, lyrical and affecting. Copland’s lithe and virtuosic arrangements from Billy the Kid and Rodeo brought the concert to a boisterous close, Terwilliger playing with nimble-fingered flair.
-The Strad

...divine phrases, impelling rhythm, elastic ensemble and stunning sounds
-Free Times (Columbia, SC)

A superior caliber of craftsmanship... The [dance] episodes displayed compelling rhythmic force and were performed colorfully by the artists... Graceful musicianship.
-The Post and Courier (Charleston, SC)


This duo stands out with their international experience and specialty in American music. Now booking Leonard Bernstein concerts for his 2018 centenary. The Duo also excels at standard music including duo concertos with orchestra.




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