A new batch of unreleased J Dilla instrumentals is set for release next month.

Curated by the late producer’s mother, Maureen “Ma Dukes” Yancey, the Motor City compilation is stacked with 19 recordings unearthed from the Dilla archives and is intended as a “letter to her son” and a tribute to his hometown of Detroit.

Physical copies of Motor City are packaged in a limited-edition mailing envelope with a hand written letter from Ma Dukes to Dilla, and are available as a CD or vinyl. Dilla collaborator J Rocc has cooked up a digital mix of the compilation that is available as a download with the purchase of the LP.

Listen to “Motor City J. Rocc Blend #1” below.

Head over to the dillatronic.com online store to place your pre-order for Motor City, out April 21.