The Digital Orchestra Toolbox for Max is an open-source collection of small modular software tools for aiding the development of Digital Musical Instruments. Each tool takes the form of an "abstraction" for the visual programming environment Max, meaning it can be opened and understood by users within the Max environment, as well as copied, modified, and appropriated as desired. This paper describes the origins of the Toolbox and our motivations for creating it, broadly outlines the types of tools included, and follows the development of the project over the last twelve years. We also present examples of several digital musical instruments built using the Toolbox.