A prolific artist who incorporates distinctive visuals and his Ecuadorian heritage into his music, Roberto Carlos Lange has worked with various collaborators and under several monikers, including Helado Negro, as well as on his own. Early projects like the funky electro collages of Epstein's 2004 debut, Puñal, and the layered post-rock of ROM's 2005 self-titled album hinted at the flair for eclectic instrumentation and atmospheres that defined his later music. Working with artists such as Prefuse 73, Savath + Savalas, and Julianna Barwick took these gifts in different directions that informed his releases as Helado Negro, which spanned the sunny musings of 2009's Awe Owe to the timely yet poetic reflections on the complex relationship between immigrant parents and their children of 2019's This Is How You Smile. Lange's work under his own name is often his most experimental music, whether it's the artful sampling of 2009's Library Catalog Music Series, Vol. 6: Music for Memory or the repurposed audio sketches of 2017's Cut Ups.

Born in South Florida in 1980 to Ecuadorian parents, Lange grew up listening to Miami bass and electro music while living in a Caribbean neighborhood. While studying computer art and animation at Georgia's Savannah College of Art and Design, he also began making music in earnest after studying sound design and audio programs in his classes. Lange made his recording debut in the early 2000s, when he released music as Epstein, as Boom Birds, and as part of the post-rock duo ROM with drummer Matt Crum. The eponymous album ROM (2005) on Wimm Recordings collected recordings dating back to 2000. During his early career, he was most prolific as Epstein, releasing the full-length albums Puñal (2004), Gente Sin Pueblo (2005), Canto de Hermanos (2007), and Otros (2008); the former two were on the label Botanica del Jibaro, the latter two on Arepaz. As Boom Birds, he released the album Camino de Manos Chuecas (2005) on Arepaz.

After moving to Brooklyn in 2006, Lange began working with Guillermo Scott Herren, earning co-production credits on the Prefuse 73 releases The Class of 73 Bells (2007) and Everything She Touched Turned Ampexian (2009) on Warp Records, plus the Savath + Savalas album La Llama (2009) and the following year's The Predicate: Dub Version on Stones Throw.

In the wake of these high-profile collaborations, Lange made his album debut as Helado Negro with Awe Owe (2009) on Asthmatic Kitty, which also featured featured Herren, Crum (also of Feathers), Jon Philpot (the frontman of Bear in Heaven), and others. That year, he also released Music for Memory, a volume of Asthmatic Kitty's library music series, under his own name. In 2011, along with releasing Helado Negro's second album, Canta Lechuza ("Owl Singing"), he appeared on Prefuse 73's The Only She Chapters.

In 2012, Lange collaborated with Julianna Barwick as OMBRE, releasing the album Believe You Me, and contributed vocals to Sinkane's album Mars. He also released another Epstein album, Sealess See. Foot Signal, a set of tracks from 2008 that ROM recorded in locales including Atlanta, Miami, and New York, also arrived that year via the German label Pingipung. Along with receiving a 2015 Joyce Award that allowed him to bring songs from Helado Negro's Island Universe Story cassette series to St. Paul, Minnesota's Ordway Concert Hall as Island Universe Story: Selected Works, that year he appeared on Certain Creatures' Vipassana. Also in 2015, Lange released Plural People, a collection of Lange's soundscapes from 1999 to 2011, and Possible Mountain, a set of ROM recordings from 2005. Helado Negro's later output included 2014's nostalgic Double Youth, 2016's Private Energy, and 2019's This Is How You Smile, all of which reflected on the themes of Latin pride and cultural awareness. Lange returned to his given name for 2017's Cutups, a collection of tracks made from previously abandoned sounds on his hard drive. ~ Heather Phares & Jason Birchmeier, Rovi