Sound Unseen: An immersive listening experience

Called “a raucous, grungy, irresistibly exuberant…fun-loving, exceptionally virtuosic family” (New
York Times), Wild Up has been lauded as one of new music’s most exciting groups by virtually every
significant institution and critic within earshot. Artistic Director Christopher Rountree started
the group in 2010 to eschew outdated ensemble and concert traditions by experimenting with
different methodologies, approaches, and contexts.
Wild Up has collaborated with an expansive list of composers, performers, and cultural
institutions. Over the last decade, the group has given milestone concerts across the United States
at the Walt Disney Concert Hall, the Hammer Museum, the Broad Museum, LACMA, The Soraya, The 92nd
Street Y, National Gallery, National Sawdust, Roulette, and many more.
Their critically acclaimed, three-time GRAMMY-nominated Julius Eastman recording anthology has been
celebrated as “a masterpiece.” (New York Times), “instantly recognizable” (Vogue), and “singularly
jubilant..a bit in your face, sometimes capricious, and
always surprising.” (NPR).

Mattie Barbier is an LA based musician and sonic researcher focused on experimental intonation, latent acoustic worlds, and the physical processes of their instrument. Their playing has been described by the LA Times as being “of intense, brilliant, virtuosic growling that gave the striking impression that Barbier was dismantling the instrument while playing it,” by the Wire as “exploring the nooks of instrumental tone far beyond the reach of most mortals,” and by the New Yorker as being a “diabolically inventive trombonist-composer.”

Barbier engages in collaborative relationships with a broad spectrum of musicians including Weston Olencki, Ellen Arkbro, Clara Iannotta, Sarah Davachi, Michelle Lou,  Wolfgang von Schweinitz,  Jacob Kirkegaard, and Katherine Young. As an interpreter they have given premieres by and collaborated with a broad spectrum of sonic practitioners including Éliane Radigue and Carol Robinson, George Lewis, Catherine Lamb, Liza Lim, Lester St. Louis, Kevin Drumm, Kaori Suzuki, Raven Chacon, Chaya Czernowin, Nate Wooley, and British pop maverick, Scott Walker. Mattie has appeared as an orchestral soloist with the Helsinki Philharmonic, SWR Symphonieorchester, and Wild Up.

Barbier is a member of RAGE Thormbones, Wild Up, echoi, Diapason, and is an active soloist and improviser on low brass instruments and bagpipes. They teach at CalArts.

Barbier has presented and created work with and for the Museum of Jurassic Technology, Getty Center and Villa, Monday Evening Concerts, Lampo, San Francisco Exploratorium, Indexical, Los Angeles Philharmonic, Bemis Center’s LOW END, Roulette Intermedium, NyMusikk, RedCat, Mahler Chamber Orchestra, Ensemble Apparat, Factory Seconds Brass Trio, and Issue Project Room as well as in collaboration with holographer Tristan Duke.  They have made a wide array festival appearances including: Borealis (NO), IMD Darmstadt (DE), Donaueschinger (DE), Musica Nova Helsinki (FI),  Maerzmusik (DE), Bludenz Tage zeitgemäßer (AT), Spor (DK), Chicago’s Frequency Festival, Dartington International Summer School (UK),  Kalv Festival (SE), JAMA (SK), Minu (DK), International Trombone Festival (CA), and the Ojai Music Festival. Mattie has held  guest residencies at a broad spectrum of institutions, including Harvard, Princeton, Stanford, Columbia, NYU, UCSD, and the University of Chicago. Various recording projects as a soloist and ensemble member have been released on Sofa Music, Dinzu Artifacts, Discreet Archive, Carrier, Tripticks, Populist, Mode, Hat Hut, Innova, Late Music, Faux Amis, Ideologic Organ, New Focus, Domino, New Amsterdam, and Kairos Records.

Cellist Ashley Walters is an internationally active performer, recording artist, conductor and educator. Praised by The Los Angeles Times for her “brilliance,” she is known for championing new repertoire, close collaboration with composers, and practices that bridge contemporary classical music, avant-garde traditions, and improvisation.

Walters maintains a diverse performance career, frequently working with microtonality, extended techniques, and alternative tunings. As a solo artist, she is recognized for tackling virtuosic, demanding works and has been the dedicatee of significant additions to the cello repertoire. She has appeared on concert series and in venues throughout the United States. Her debut solo album, Sweet Anxiety, was released in 2017 on Populist Records to critical acclaim.

A frequent collaborator with legendary trumpeter, improviser, and composer Wadada Leo Smith, Walters joined his Golden Quintet in 2016, recording America’s National Parks that same year. The album was named Jazz Album of the Year in DownBeat Magazine’s 65th Annual Critics Poll and selected as one of Nate Chinen’s Best Albums of 2016 in The New York Times. With Smith, she has toured nationally and internationally and appears on three albums: America’s National Parks, Rosa Parks: Pure Love, and String Quartets Nos. 1–12.

Walters is a member of the Formalist Quartet, Wild Up, and Echoi, the performing ensemble of the renowned Monday Evening Concerts. An active conductor, she leads operatic, orchestral, and contemporary chamber music in both performance and recording.

As a full-time faculty member at Ventura College, Walters conducts the Symphony Orchestra, directs chamber music, and teaches cello, conducting, and music theory. She is passionate about connecting the college with the broader community through educational and community outreach events, as well as the Allegro Solo Competition, which she founded in 2024. She also serves as Director of the Ventura College Schwab Academy of Music, a summer intensive for orchestral and chamber music that presents six concerts, including the final round of the Henry Schwab Violin and Viola Competition. 

Dr. Walters holds degrees from Vanderbilt University, California Institute of the Arts, and UC San Diego and lives in Ventura, California.

Clarinetist and composer Brian Walsh frequently performs with such diverse groups as
Brightwork newmusic, Wild up Modern Music Collective, and the Josh Nelson Discoveries
Group. He also leads Walsh Set Trio, a jazz ensemble focusing on the performance of his own
compositions.

The Los Angeles Times has described Walsh’s playing as “spectacular”, as well as having
“found the essence of a licorice stick’s lyrical limberness, often murmuring and wailing at the
same time”. Walsh has performed as a guest artist with the Los Angeles Philharmonic’s Green
Umbrella new music series at Walt Disney Concert Hall and is a frequent collaborator on the
Monday Evening Concerts and Tuesdays at MonkSpace concert series. He has also performed
extensively with Long Beach Opera and The Industry.

Walsh has premiered pieces by Luigi Nono, Anne LeBaron, Girard Grisey, James Newton,
Andrew Nathaniel McIntosh, Wayne Shorter, Tom Johnson and many others. He has
collaborated or performed with Esperanza Spalding, Flea, Peter Maxwell Davies, Meredith
Monk, Vinny Golia, Nicholas Deyoe, Gavin Bryars, Bobby Bradford, Bright Eyes, San Fermin,
Andrea Bocelli, James Newton, and Muhal Richard Abrams.

Linnea Powell enjoys a multifaceted career as a freelance chamber, orchestral and studio violist in the Los Angeles area. An avid interpreter of new music, Powell is a member of the GRAMMY nominated ensemble Wild Up and often performs with Monday Evening Concerts, WasteLAnd, Brightwork Ensemble, and the Salastina Music Society. Powell actively commissions and records new works as the violist and co-founder of Aperture Duo, which was listed as “Best of Bandcamp” and has been regularly featured on LA Phil’s Noon to Midnight series. 

Powell serves as Principal Viola for touring Broadway productions at the Ahmanson and Pantages Theater. She has recorded and performed with such legendary artists as Bjork, The Beatles, John Wiliams, and Van Dyke Parks, and records frequently for the film and television industry.

Andrew McIntosh is a Grammy-nominated violinist, violist, baroque violinist, and composer who teaches at the California Institute of the Arts and is a member of Wild Up, Formalist Quartet, Red Koral Quartet, Echoi (Concertmaster), Tesserae (Concertmaster), and Bach Collegium San Diego. Modern repertoire is an important part of McIntosh’s musical life, and recent performances include the premieres of significant new works by La Monte Young, Wadada Leo Smith, and Éliane Radigue/Carol Robinson, among others.

As a baroque violinist he has served as guest concertmaster for operas with LA Opera and Opera UCLA, and in 2023 served as both Music Director and Concertmaster of Long Beach Opera’s all-Handel pastiche production “The Feast,” a collaboration with Martha Graham Dance Company. About a recent performance of the complete Rosary Sonatas of Heinrich Biber at the 92nd Street Y, the New York Times said “his playing had exceptional clarity and rhetorical verve”. His recording of the sonatas for violin and fortepiano of Joseph Bologne, Chevalier de Saint-Georges with Steven Vanhauwaert was released in November 2023 on Olde Focus Records.

As a composer he was described by Alex Ross in the New Yorker as “a composer preternaturally attuned to the landscapes and soundscapes of the West”, and recent commissions include works for the LA Philharmonic, Yarn/Wire, Wild Up, Miller Theatre at Columbia University, Vicki Ray, and violinist Ilya Gringolts. Portrait albums of his music can be found on KAIROS, Populist Records, and Another Timbre.

M.A. Tiesenga is a multi-instrumentalist and sound artist currently residing in Los Angeles. Tiesenga specializes in work with saxophones and improvisation, balancing virtuosity with creativity. Tiesenga is a prolific and dedicated proponent of new music and interdisciplinary collaborations, maintaining a diverse career spanning between experimental music, soul, pop, jazz, classical, and session recording. They have been seen making music at the Walt Disney Concert Hall, Hollywood Bowl, on TV, in caves, and remote pastures.

Tiesenga’s creative collaborations include work with the Los Angeles Philharmonic, Wild Up, Ojai Music Festival, Bang On A Can All-Stars, Monday Evening Concerts, Civic Orchestra of Chicago, High Desert Soundings, Brightwork New Music, WasteLAnd, Théâtre Musical Tokyo, Long Beach Opera, Kunsthalle for Music, SPEAK Percussion, Ensemble Ipse, Dog Star Orchestra, Ung Nordisk Musik, Ensemble Supermusique, and ensembles at the Eastman School of Music, New England Conservatory, California Institute for the Arts, Yale University, and Darmstädter Ferienkurse.  

Tiesenga holds an MFA in Experimental Sound Practices and an MFA in Experimental Animation with a Concentration in Integrated Media from California Institute of the Arts, where they studied with Michael Pisaro, Sara Roberts, Eyvind Kang, Alexander Stewart, Pia Borg, and Tom Leeser. Previously, Tiesenga earned a Bachelor of Music from the Eastman School of Music in saxophone performance under the guidance of Dr. Chien-Kwan Lin.