Cantus is widely known for its trademark warmth and blend, innovative programming and engaging performances of music ranging from the Renaissance to the 21st century. The Washington Post has hailed the Cantus sound as having both “exalting finesse” and “expressive power” and refers to the “spontaneous grace” of its music making. The Philadelphia Inquirer called the group nothing short of “exquisite.”

Cantus performs more than 60 concerts each year both in national and international touring, and in its home of Minneapolis/St. Paul, Minnesota. As one of the nation’s few full-time vocal ensembles, Cantus has grown in prominence with its distinctive approach to creating music. Working without a conductor, the members of Cantus rehearse and perform as chamber musicians, each contributing to the entirety of the artistic process.

Committed to the expansion of the vocal music repertoire, Cantus actively commissions new music and seeks to unearth rarely performed repertoire for men’s voices. The ensemble is heard frequently on both classical public radio nationwide and on SiriusXM Satellite Radio. Cantus has released 18 recordings on the group’s self-titled label.

Integral to the Cantus mission is its commitment to preserve and deepen music education in the schools. Cantus works with more than 5,000 students each year in master class and workshop settings across the country. For more information visit

Dale Trumbore is a Los Angeles-based composer and writer whose music has been praised by The New York Times for its “soaring melodies and beguiling harmonies.” Her music has been widely performed in the U.S. and internationally by ensembles including the Los Angeles Children’s Chorus, Los Angeles Master Chorale, Pacific Chorale, Pasadena Symphony, The Singers – Minnesota Choral Artists, and VocalEssence. She has served as Composer in Residence for Choral Chameleon and Nova Vocal Ensemble. Choral Arts Initiative’s debut album of her choral works, How to Go On, debuted at #6 on Billboard’s Traditional Classical Chart. Trumbore has written extensively about working through creative blocks and establishing a career in music in essays for 21CM, Cantate Magazine, the Center for New Music, NewMusicBox, and in her book Staying Composed: Overcoming Anxiety and Self-Doubt Within a Creative Life. Learn more at

Carol Barnett’s music has been called audacious and engaging. Her varied catalog includes works for solo voice, piano, chorus, diverse chamber ensembles, orchestra, and wind ensemble.

She was awarded the 2003 Nancy Van de Vate International Prize for Opera for her chamber opera, Snow, and her music theater work Meeting at Seneca Falls was featured at the 2006 Diversity Festival in Red Wing, MN. The World Beloved: A Bluegrass Mass, commissioned in 2006 by VocalEssence and written with Marisha Chamberlain, had its Carnegie Hall debut in February 2013 and has become a favorite across the country. Recent works include Coy Pond Suite for the Gordon College Big Band; Mortals & Angels: A Bluegrass Te Deum for the Distinguished Concerts International New York Festival Chorus and bluegrass band Dailey & Vincent; and Musica, dei donum optimi for the Rose Ensemble.

Barnett is a charter member of the American Composers Forum and a graduate of the University of Minnesota, where she studied composition with Dominick Argento and Paul Fetler. She was composer-in-residence with the Dale Warland Singers from 1992 to 2001, and was an adjunct faculty member at Augsburg College from 2000 to 2015. Further information is available at

David von Kampen (b. 1986) is a composer based in Lincoln, Nebraska. David’s creative work spans a wide variety of genres and styles, including jazz, choral music, hymnody and liturgy, solo voice, chamber music, and musical theater.

David is a six-time Downbeat Award winner in graduate-level jazz writing categories, a three-time winner of the Vancouver Chamber Choir Young Composers Competition, and was named the MTNA Distinguished Composer of the Year for his song cycle “Under the Silver and Home Again.” He has been among ten winners of the ORTUS International New Music Competition, the recipient of an ASCAP Young Jazz Composer award, winner of the San Francisco Choral Artists New Voices Project, winner of the National Band Association’s Young Jazz Composers Competition, and received Honorable Mention in the New York Youth Symphony First Music Commissions. “Puddin’ and the Grumble,” David’s original musical with playwright Becky Boesen, was one of seven finalists for the Richard Rodgers award.

His music has been performed by the KHORIKOS Vocal Ensemble, the L.A. Choral Lab, KC VITAs Chamber Choir, the Taiwan Youth Festival Chorus, San Francisco Choral Artists, the U.S. Army Blues Jazz Ensemble, the Vancouver Chamber Choir, and by collegiate, all-state, high school, and church ensembles throughout the United States and internationally.

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Joshua Shank’s works have been widely performed by educational and professional ensembles alike.  His music has been called “jubilant…ethereal” (Santa Barbara News-Press) and “evocative and atmospheric” (Gramophone).  The Boston Classical Review called his Magnificat for the Mothers of the Plaza de Mayo “powerful” and “emotionally charged.”  He has been commissioned by ensembles such as Conspirare, the Young New Yorkers’ Chorus, the Cincinnati Conservatory of Music, the American Choral Directors Association, The Esoterics, and the Lorelei Ensemble. From 2004 to 2014, he served as Composer-In-Residence for the Minneapolis-based professional choir, The Singers.  During that time, he collaborated annually with fellow composers-in-residence Jocelyn Hagen and Abbie Betinis to expand and invigorate the repertoire for professional-caliber ensembles through innovative programming as well as new works written specifically for the choir.

In 2002, he became the youngest recipient ever of the Raymond W. Brock Composition Award by the American Choral Directors Association. The winning piece, “Musica animam tangens,” was premiered in Avery Fisher Hall at the Lincoln Center, and has since been performed and recorded from Los Angeles to South Africa.  His music was recently featured in a documentary about the extensive choral tradition in the upper Midwest, Never Stop Singing, and his published works have sold over 150,000 copies worldwide.  

Joshua received his undergraduate degree in Vocal Music Education from Luther College in Decorah, Iowa where he studied conducting with Weston Noble and composition with John Morrison and Neil Flory.   He earned master’s and doctoral degrees in composition at the University of Texas at Austin where he studied with Dan Welcher, Yevgeniy Sharlat, Russell Pinkston, Donald Grantham, and the late opera composer Daniel Catán.  A native of Minnesota, Joshua currently teaches music theory and composition as well as conducts the Men’s Chorus at Gonzaga University in Spokane, Washington.

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Founded in 2006, Graphite Publishing is an online vocal music publisher of digital scores. Graphite publishes quality compositions where excellence and accessibility meet: unique yet emotional; challenging yet appealing; innovative and enjoyable to experience. Representing some of the leading composers of choral music and art song, Graphite has been central in paving the way for digital publishing and distribution.

In addition to it’s own cultivated roster of composers and curated catalog of over 120 pieces, Graphite also distributes the music of select independent publishers and composer/publishers through it’s online Marketplace.

The mission of The NDSU Challey School of Music is to provide academic programs and artistic performances that serve our students through professional preparation and fine arts enrichment. The School also strives to serve the world-wide community through the excellence of our widespread performances, opportunities and endeavors. The Choral Series is part of the mission to serve our world-wide community of musicians and supporters.

One of the goals of the NDSU Challey School of Music Choral Series is to enable the creation of quality choral music for all types of choirs. The music selected for this series has a wide range of voicings and difficulties which can meet the needs of choral musicians everywhere. The NDSU Challey School of Music Choral Series is committed to publishing high-quality choral music written by composers and arrangers who believe in the power that choral music has to enrich and enhance the lives of all.

Choral music at NDSU has had a long tradition of excellence in choral music. Edwin Fissinger was the Director of Choral Activities and brought national acclaim to the NDSU Concert Choir. Jo Ann Miller is the current Director of Choral Activities and has continued that tradition of excellence, both on a national and international scale. The NDSU Challey School of Music Choral Series also honors our long tradition of excellence in the choral art.

Composer Timothy Hoekman has written in many genres, but most of his works include the voice.  His works have been published by Theodore Presser, Colla Voce, Plymouth Music Company, Recital Publications, and Classical Vocal Reprints.  He was named the 2002 MTNA-Shepherd Distinguished Composer of the Year for his song cycle To Make a Prairie, commissioned by the South Dakota Music Teachers Association.  Other commissions have come from the Rawlins Piano Trio, the Coastal Carolina Chamber Music Festival, Georgia Southern University, and First Presbyterian Church of Tallahassee, among others.  His works have been recorded for Albany Records, Azica Records, and Mark Records.

Hoekman is Professor of Vocal Coaching and Collaborative Piano at Florida State University.  He is a highly experienced performer, teacher, and coach, having performed as soloist and collaborative pianist in the U.S., Canada, Australia, and Europe.  He was on the music staff of Glimmerglass Opera in Cooperstown, NY, from 1988 to 2011 and has also worked for South Georgia Opera, Florida Grand Opera, Des Moines Metro Opera, Michigan Opera Theater, Opera Grand Rapids, and the Peter Harrower Summer Opera Workshop.  He currently spends summers as the head lieder coach for the American Institute of Musical Studies in Graz, Austria.  He has been at FSU since 1984, teaching collaborative piano, coaching graduate voice majors, and teaching a variety of language and vocal literature classes for singers and pianists. He has served as adjudicator for vocal, piano, and composition competitions.

Hoekman holds degrees from the University of Michigan, Peabody Conservatory, and Calvin College. He has written articles for the Journal of Singing, American Music Teacher; and Voices: Opera America’s Bulletin for Singers.

For more information about Timothy Hoekman and his compositions, visit

Deemed “indesputably unique, confident, and innovative” through the American Prize, Paul John Rudoi’s award-winning compositions have been commissioned and performed by various ensembles and artists throughout North America and Europe, including Orphei Dränger, the Vancouver Chamber Singers, the British Trombone Society, Cantus, and the National Lutheran Choir. His work has garnered numerous grants from the Jerome Foundation, the ACF, MRAC, MSAB, the NEA, and ASCAP. His music is published through PJR Music alongside Graphite, Santa Barbara, Walton, Morningstar, and ECS music publishers.

As a professional tenor vocalist, Paul has performed and recorded a wide range of music as a member of the full-time vocal ensemble Cantus. From 2008-2016, he premiered dozens of new works for male chorus, toured on four continents, and advocated for arts education and empowerment through education outreach opportunities nationwide.

Paul holds a degree in Vocal Performance from the Hartt School and is pursuing a concurrent master’s in Choral Conducting and Composition from the University of Oregon. His teachers have included Sharon Paul, Robert Kyr, Libby Larsen, Edward Bolkovac, and Tyler Flanders. Visit for more information and for a complete catalog of works.

Performed on four continents, Linda Tutas Haugen’s music has been critically acclaimed as “music of character and genuine beauty.” [Minneapolis StarTribune.] Opera Today praised her opera, Pocahontas, as “superbly crafted,” “engaging,” and “beautiful and powerful.” She has written for instrumental and vocal chamber ensembles, symphony orchestra, wind ensemble, solo voice, chorus and opera.

Linda has received national awards, fellowships and commissions from American Composers Forum, American Guild of Organists, ASCAP, Meet The Composer, NEA, San Francisco Girls Chorus, and Virginia Arts Festival/Virginia Opera, and regional awards from the Minnesota State Arts Board, the Bush, and Jerome foundations. Performers of her works include Saint Paul Chamber Orchestra, North Carolina Symphony and Chiara String Quartet. Her choral music has been performed by junior and senior high school, university and adult choirs throughout the U.S., in Europe, Korea and Australia.

A frequent visiting Composer-in-Residence, Linda works collaboratively with ensembles and schools to champion the creative process and new music. She enjoys working with performers, speaking about the compositional process, and the deeper implications and need for art in today’s society. She served for the past two years as Composer-In-Residence for the National Lutheran Summer Music Institute and Festival at Luther College. Recent presentations at conferences have included To Change the World (NCCO), and Musical Faith Partners (American Cantors Conference). She is a founding member of Independent Music Publishers Cooperative, and she loves 26 degree days with sunshine and sparkling snow.

Jocelyn Hagen composes music that has been described as “simply magical” (Fanfare Magazine) and “dramatic and deeply moving” (Star Tribune, Minneapolis/St. Paul). Her first forays into composition were via songwriting, and this is very evident in her work. The majority of her compositional output is for the voice: solo, chamber and choral. In 2015, Test Pilot, her dance opera collaboration with choreographer Penelope Freeh, received a Sage Award for “Outstanding Design,” and the panel declared the work “a tour de force of originality.” Her melodic music is rhythmically driven, texturally complex, and has recently become more experimental in nature. In 2013 she released an EP entitled MASHUP, in which she performs Debussy’s “Doctor Gradus Ad Parnassum” while singing Ed Sheeran’s “The A Team.”

Her commissions include Conspirare, The Minnesota Orchestra, the American Choral Directors Associations of Minnesota, Georgia, Connecticut and Texas, the North Dakota Music Teacher’s Association, Cantus, the Boston Brass, The Metropolitan Symphony, and The Houston Chamber Choir, among many others. She is currently an artist-in-residence at North Dakota State University and regularly composes for their ensembles. For ten years she was a composer-in-residence for the professional choir she also sang in: The Singers, under the direction of Matthew Culloton. Her music has been performed all over the world, including Carnegie Hall and Lincoln Center in New York City. Her work is independently published through JH Music, as well as Graphite Publishing, G. Schirmer, Santa Barbara Music Publishing, Fred Bock Music Publishing, and Boosey and Hawkes.

Visit for more information and a complete catalog of works.

J. David Moore is a composer, arranger, conductor, teacher, and Southerner who has lived in the Upper Midwest for most of his life. His music has been called “endlessly inventive,” “glorious…haunting…breathtaking,” and “joyous…wild and elemental.” He publishes through his company Fresh Ayre Music, and is the founder and conductor of The First Readings Project, a chamber choir that acts as a resource for composers in the development and promotion of new work.

He lives with his wife Anna in Minneapolis, where he bakes bread, drinks tea, and is distracted by beauty.

A conductor and composer, Eric William Barnum continues to passionately seek new ground in the choral field. Working with choirs of all kinds, his collaborative leitmotif endeavors to provide intensely meaningful experiences for singers and audiences.

Barnum is currently the Director of Choral Music at the University of Wisconsin, Oshkosh. He holds a DMA in Choral Conducting from the University of Washington (Seattle, WA), under the direction of Dr. Geoffrey Boers. He has an advanced degree in conducting from Minnesota State University (Mankato, MN), primary study with Dr. David Dickau, as well as BAs in Composition and Vocal Performance from Bemidji State University (Bemidji, MN). He has appeared as a conductor across the United States, and has had the opportunity to work with some of the most innovative minds in the choral field.

His voice and vision continues to gain popularity around the globe with performances from choirs internationally. He composes for choral ensembles of all types, from professional to youth choirs, and has received numerous awards and prestigious grants such as a Bush Foundation Artist Fellowship and a McKnight Foundation Grant. He has also held residencies with such ensembles as Choral Arts (Seattle, WA), The Rose Ensemble (St. Paul, MN), Kantorei (Denver, CO), Magnum Chorum (Minneapolis, MN), Coro Vocal Artists (Tucson, AZ), as well as with many high schools and collegiate choirs.

Elizabeth Alexander (b. 1962) grew up in the Carolinas and Appalachian Ohio. Her love of music, language and challenging questions is reflected in her catalog of over 100 songs and choral works, and a style which moves effortlessly between concert stage, choir loft and jam session. Her music has been performed by soloists, chamber musicians and orchestras around the world, as well as by thousands of choirs.

Her acclaimed text settings of both original lyrics and the words of others prompted Choral Director Magazine to write that her “mastery of prosody and declamation results in a marriage between music and text that is dynamic and indelible.” Other reviewers have described her music as “brilliantly innovative” (New York Concert Review), “truly inspired” (Boston Intelligencer) and “stunning…exquisite…sculpting light into sound” (Kansas City Metropolis).

Elizabeth’s many commissions have included works for orchestra, chamber ensembles, solo instruments and voice, but she is best known for her choral pieces, which have been performed by thousands of choruses worldwide. A recent McKnight Composition Fellow, she has also received grants, awards and fellowships from the Jerome Foundation, New Music USA, Minnesota State Arts Board, New York Council on the Arts, Wisconsin Arts Board, National Orchestral Association, International League of Women Composers, American Composers Forum. She studied composition with Steven Stucky, Jack Gallagher, Yehudi Wyner and Karel Husa, receiving her doctorate in Music Composition from Cornell University.

She lives in Saint Paul, Minnesota, where she reads voraciously, makes pretty good biscuits, looks for all kinds of excuses to visit her two grown sons, and gardens during the three month period in Minnesota which is not winter.

The music of young American composer Dominick DiOrio has been called “a tour de force of inventive thinking and unique colour” (Gramophone) and “[full of] sunny rays of heavenly light” (Opera News). In 2014, he was named the winner of The American Prize in Composition with the judges saying “his depth of vision, mastery of compositional technique, and unique style set him in a category by himself.” DiOrio’s music is widely performed, published, and recorded, having been presented in major venues across the United States as well as in Austria, Canada, China, Hong Kong, Korea, Sweden, and the UK. His works are published with Boosey & Hawkes, Carl Fischer, G. Schirmer, Oxford, and others; and they can be heard on albums released with Divergence, MSR Classics, Naxos of America / Seraphic Fire Media, and New Dynamic Records.

Also an accomplished conductor, DiOrio is the youngest-ever tenured member of the conducting faculty at the Indiana University Jacobs School of Music. He is the director of NOTUS, an elite chamber chorus that specializes in performing and commissioning new music of living composers. DiOrio earned the DMA, MMA, and MM degrees in conducting from the Yale School of Music, and the BM in composition from Ithaca College. He currently serves as Treasurer for the National Collegiate Choral Organization, as a member of the Board of Directors for Chorus America, and on the ACDA Composition Initiatives Standing Committee. For more information and a full catalog visit

With CORO Publishing, CORO has created an innovative way to encourage new choral publications to be written for the choral community. CORO Publishing actively seeks new and unpublished choral works of the highest level, as well as modern editions of earlier works. With new choral pieces, we focus mainly on octavos for unaccompanied chorus and chorus with piano or small instrumental ensembles. CORO Publishing also looks to the standard choral repertoire of the western canon and creates new editions in order to bring these compositions to a broader range of modern performers and audiences alike.

When working with a composer on a new composition, CORO Publishing is in a unique situation by being directly linked with the CORO Vocal Artists; from the beginning, a dialogue is opened between the composer and the conducting staff of CORO. This dialogue allows these new compositions to be rehearsed with the CORO Vocal Artists and fine tuned while in the final stage of composition. CORO Vocal Artists record these new publications for commercial distribution in audio and video formats and the octavo is then published through CORO Publishing. CORO Publishing actively searches for compositions that meet these requirements as well as establishing relationships with other publishing companies that would benefit from the collaborative nature of CORO.

VocalEssence Music Press is a dynamic music publishing company that offers a select group of emerging composers the opportunity to make their music available to choirs everywhere. And we offer choruses access to new music they can’t find anywhere else.

Our mission is to help choruses, conductors and composers connect in meaningful ways by publishing exciting new music for singers at all levels.

Discover cross-cultural collaboration through the VocalEssence ¡Cantaré! Series. Mexican composers wrote these works for Minnesota school, college and community choruses to sing. Even young children can master the challenge of singing in Spanish and the indigenous languages of Mexico. Get value-added with our free Music Resource Guides that are designed for conductors, teachers and students to use to learn more about the cultural context of the compositions.

VocalEssence Music Press is a subsidiary of VocalEssence, a leading arts organization based in Minneapolis, Minnesota.

Heralded for its “warm, lithe, and beautifully blended” sound (New York Times) “impeccable musicality” (Boston Globe) and unfailing display of the “elegance, power, grace, and beauty of the human voice” (Boston Musical Intelligencer) Boston’s Lorelei Ensemble is quickly becoming recognized as a source of some of the most innovative and inventive programming in Boston and beyond. Lorelei is an all-professional vocal ensemble, comprising nine women whose expertise ranges from early to contemporary repertoire, and whose independent careers as soloists and ensemble singers across the globe lend to the rich and diverse vocal palate that defines the ensemble’s consistent delivery of “exact, smooth, and stylish” programming (Boston Globe).

Committed to the expansion of the repertoire for women’s voices, Lorelei has commissioned and premiered more than fifty new works since its founding in 2007, and continues to expose and reinvent early works of the Medieval, Renaissance, and Baroque repertoires. Driven by their mission to advance the women’s vocal ensemble and enrich the vocal repertoire through forward-thinking and co-creative collaboration, Lorelei works with established and emerging composers from the United States and abroad to create new works that reveal the extraordinary flexibility and strength of the human voice.

In its publication series, Lorelei seeks to present editions of some of its commissioned works. The works chosen are pieces that have broad usefulness and appeal to other women’s vocal ensembles and choruses.

Joan Szymko (b.1957) is a composer and conductor living and working in Portland, Oregon where she is entering her 23rd season as the Artistic Director of Aurora Chorus. As a frequently commissioned composer with a catalog of over 100 published choral works, her music is performed by ensembles across North America and abroad. Since 2003, her music has been performed at every National Conference of the American Choral Directors Association. In 2010 the ACDA recognized Szymko’s lasting impact on the choral arts in America by selecting her as the recipient of the Raymond W. Brock Memorial Commission. Joan enjoyed a fruitful, decade-long collaboration with Robin Lane and Do Jump! Movement Theater (1994-2004) performing her original music with the company in Portland and touring on Broadway, at the Kennedy Center and at the Geffen Playhouse in LA. She has served on the choral music faculty at Portland State University (2013-15). As a visiting artist, she workshops her music with choirs in a variety of educational settings across the US and most recently, in the Netherlands.

Szymko was recently commissioned by Eugene Vocal Arts (Oregon) to create the libretto and compose a large scale work which focuses on those faced with the tragedy of Alzheimer’s dementia. “Shadow and Light” for mezzo-soprano, tenor, soprano, SATB chorus and full chamber orchestra premiered in April 2016 to great critical acclaim. This notable addition to the choral-orchestral repertoire will be made available by Joan Szymko Music in 2017. In addition to her own published works, Joan’s music appears in the catalogs of Santa Barbara Music Publishing, Lorenz Corporation (Roger Dean Publishing), earthsongs, Treble Clef Press and Walton Music. She is a founding member of the Independent Music Publishers Cooperative.

Reviewed as “gorgeous” (Washington Post) and “stunning” (Lawrence Journal-World), the music of Timothy C. Takach has risen fast in the concert world. Applauded for his melodic lines and rich, intriguing harmonies, Takach has received commissions from various organizations including the St. Olaf Band, Cantus, Pavia Winds, Lorelei Ensemble, The Singers: Minnesota Choral Artists, VocalEssence, the DeBartolo Performing Arts Center, The Rose Ensemble, and numerous high school and university choirs. His compositions have been performed on A Prairie Home Companion, The Boston Pops holiday tour, multiple All-State and festival programs and at venues such as the Library of Congress, Kennedy Center and Royal Opera House Muscat. Takach has received grants from the American Composers Forum, Meet the Composer, Minnesota State Arts Board, Metropolitan Regional Arts Council, and ASCAP.

He is a co-creator of the theatrical production of All is Calm: the Christmas Truce of 1914, by Peter Rothstein. The critically adored show has had over 100 performances since it’s premiere in 2006. He was also selected for the 2014 Nautilus Music-Theater Composer-Librettist Studio. Takach independently publishes his own music and is also a co-founder of Graphite Publishing along with Jocelyn Hagen.

Takach studied music composition at St. Olaf College, Northfield, MN, where he graduated with honors. He has frequent work as a composer-in-residence, presenter, clinician and lecturer for conventions, schools and organizations across the country. He is a full-time composer and lives in Minneapolis with his wife and two sons.

1: (Easy) No divisi in voice parts, accompaniment doubles or supports vocal parts, diatonic, symmetrical phrases, textures mostly homophonic, simple rhythms, stepwise voice leading (conjunct), moderate ranges, no extended techniques, and limited sustained singing.

2: (Medium Easy) Limited divisi, voices somewhat independent from accompaniment, some chromatics, phrases may be longer or more fragmented, mostly homophonic, moderate rhythmic complexity, some difficult intervals (disjunct motion), moderate ranges, extended techniques are simple, limited sustained singing.

3. (Medium) Limited divisi, unaccompanied, or with independent accompaniment (voice parts not doubled), many chromatics, phrases of varying lengths, more contrapuntal textures, moderately complex rhythms, some difficult intervals (disjunct motion), moderately difficult/challenging ranges, extended techniques are potentially challenging, and some sustained singing.

4. (Medium Difficult) Abundant divisi, unaccompanied, or accompanying instruments are fully independent from voice parts, many chromatics and/or key changes, long and/or broken phrases, potentially little homophony, complex rhythms, many difficult intervals (disjunct motion), difficult/challenging ranges, potentially difficult extended techniques, and a demand for sustained singing.

5. (Difficult) Adundant divis, unaccompanied, or accompanying instruments are fully independent from voice parts, many chromatics and/or key changes, long and/or broken phrases, potentially little homophony, complex rhythms, extreme ranges, use of challenging or unusual extended vocal techniques, abundant sustained singing.