In April of 2001 Brad co-founded The Creaking Tree String Quartet. The acoustic quartet also features the work of John Showman (fiddle), Brian Kobayakawa (double bass) and Andrew Collins (mandolin). The C.T.S.Q. debut self titled CD was nominated for Roots and Traditional Album of the Year: Group, at the 2004 JUNO Awards. Their second CD "Side Two" won Instrumental Album of the year at the Acoustic Project Awards and "Old Crow" (the second track on "Side Two") won Instrumental Song of the Year at the International Acoustic Music Awards. This CD also won the "Pushing the Boundaries" trophy at the inaugural Canadian Folk Music Awards. Their Third CD "The Soundtrack" won two Canadian Folk Music Awards in the Best Instrumental Group and Pushing the Boundaries categories, and was also nominated for Instrumental Album of the Year at the 2009 JUNO awards.

Brad has Performed throughout Canada and the U.S. including such geographically diverse locals as the N.W.T, the Yukon and Newfoundland in Canada, and large urban centers such as Manhatten, Boston, Philadelphia, Portland and Seattle in the US. He has performed at a wide range of venues including: The Atlantic Jazz Festival, The Ottawa Blues Festival, The Ottawa International Chamber Music Festival, The Calgary Folk Festival, The Montreal Jazz Festival, The Stratford Concert Series, Seattle Folk Life, The Vancouver Folk Festival, The Winnipeg Folk Festival and twice on the Roots and Branches Stage at the I.B.M.A. (International Bluegrass Music Association) Fan Fest, once in Louisville, Kentucky, and the other in Nashville, Tennessee.

In early Oct "09 thanks to a generous grant from the Canada Council for the Arts. Brad released his first CD under his own name entitled "House On Fire". Keller decided to assemble some of Torontos finest musicians to perform his latest compositions featuring a variety of different instumentations including Piano Clamhammer Banjo Fiddle Mandolin Tenor Sax and B3 Organ. House On Fire is an All-Instrumental release written and performed primarly on the acoustic guitar but also displays some of Brad's soulful electric guitar skills. This recording named itself when the house the studio was in caught on fire as the musicians were busy recording (not just a little fire but the flames were over 4 feet high at one point and the entire house was almost lost including the instruments and everything that was recorded already!!!).'