An active chamber musician, he has performed in many chamber ensembles with musicians including Mitsuko Uchida, Richard Goode, Miriam Fried, Pamela Frank, Anthony Marwood, Donald Weilerstein, Kim Kashkashian, Roger Tapping, Atar Arad, Bonnie Hampton, Marcy Rosen, Peter Stumpf, Peter Wiley, Paul Katz, Timothy Eddy, and Laurence Lesser. He has appeared at festivals including Marlboro, Caramoor's Rising Stars Series, Ravinia, ChamberFest Cleveland, Prussia Cove's Open Chamber Music, Yellow Barn, Moab, Menuhin Festival Gstaad, Siete Lagos (Argentina), Frutillar (Chile), and with the Israeli Chamber Project.

David was born in Santa Rosa, California in 1986 and began studying the violin with Helen Payne Sloat at the age of 4. At 8, he attended the Crowden School of Music in Berkeley studying with Anne Crowden. When David was 13, he received an invitation to join the Yehudi Menuhin School outside London where he studied for five years with Simon Fischer. David continued his studies with Donald Weilerstein and Miriam Fried at New England Conservatory of Music in Boston and with Antje Weithaas in the Konzertexamen program at the Hanns Eisler Academy in Berlin.

In addition to music, David maintains an active interest in social concerns including the needs of those impacted by the AIDS pandemic and is currently working on projects of the Starcross Community to help AIDS orphans in Africa. He has played in programs promoted by the Fellowship of Reconciliation and has given benefit concerts for Doctors Without Borders. With other members of his family, David has worked to get strings to young music students in Cuba where such items are very difficult to obtain. David plays a 1761 violin made by A & J Gagliano.

He then studied piano with George Sementovsky in Philadelphia and graduated summa cum laude from Temple University's Esther Boyer College of Music in Philadelphia. He was subsequently awarded a fellowship to the Eastman School of Music in New York where he received a Doctor of Musical Arts degree in Piano Performance and Literature.

Thereafter, he won praise in many international piano competitions and received top honors in the Artist International Competition which led to his New York debut recital at Carnegie Hall and the Gold Medal at the New Orleans International Piano Competition. In 2009, he was selected as an International Steinway Concert Artist, and since then has performed in England, Ireland, Italy, Germany, Canada, and throughout the United States.

Following his performance at the prestigious Reading Festival in England, International Piano Magazine wrote, "D'León's recital was an absolute sheer and dazzling delight!" His summers have included performances at the Banff Festival in Canada, Boyle Festival in Ireland, Schlern Festival in the Italian Alps, and Mendocino Music Festival on the northern California coast.

As a chamber musician, he has performed with many of the world's finest chamber groups including the Muir String Quartet and Shanghai String Quartet. He has given master classes at more than 75 universities around the world and has served as judge in international piano competitions for pianists of all ages.

As a recording artist, the American Record Guide calls his performances "Remarkably played! The result is a revelation and a real treasure!" E-Music Magazine calls his performance of Schubert and Liszt "Amazing…and if you think you have heard it all with this particular Schubert sonata, take a listen to this disc!" He has recorded contemporary works for the German Col Legno label, including works by renowned Czech composer Ladislav Kubik. Upcoming projects include the first recording of Argentine composer Ástor Piazzolla's complete tangos transcribed for piano quintet.

Oliver has worked with renowned conductors such as Michael Tilson Thomas, Juanjo Mena, and Yannick Nézet-Séguin. As a chamber musician, Oliver has performed with some of the leading musicians of our time including Shmuel Ashkenasi, Franklin Cohen, Pamela Frank, Miriam Fried, Nobuko Imai, and Meng-Chieh Liu. In addition, Oliver frequently collaborates with pianist Xiaohui Yang as a recital duo. This season, they will perform on tour in both the United States and Greece.

Oliver is frequently invited to participate in music festivals including the Caramoor Festival, ChamberFest Cleveland, Krzyżowa Music, Music in the Vineyards, Open Chamber Music at IMS Prussia Cove, the Ravinia Festival Steans Music Institute, and the Verbier Festival Academy. In addition to being a fellow at the Ravinia Festival, Oliver was also invited to perform on a tour with renowned violinist Miriam Fried, the festival's director. At the 2017 Verbier Festival, Oliver was awarded the Prix Jean-Nicolas Firmenich. He has also appeared on NPR's From the Top.

Oliver's most recent competition awards include a top prize and special prize in the XI Witold Lutoslawski International Cello Competition in 2018, first prize and Pablo Casals prize in the 2015 Irving M. Klein International String Competition, and a top prize in the 2015 Stulberg International String Competition.

Oliver is a graduate of the Curtis Institute of Music where he studied with Carter Brey and Peter Wiley. Before starting his studies at Curtis, Oliver was a student of Clive Greensmith at the Colburn School. In addition, he has been greatly inspired by his studies with Pamela Frank and Dr. Ford Lallerstedt at the Curtis Institute, as well as his sessions with Steven Isserlis at IMS Prussia Cove. He currently plays on a 1769 Guadagnini cello that belonged to the great Italian cellist Antonio Janigro, on generous loan from the Janigro family.