The NeXT Computer system software release 3.0 includes a new Mach device driver that controls the sound playback and recording hardware. Also new are several software objects in the sound kit that provide direct access to the driver. Included are objects that represent the hardware devices themselves, and objects that implement streams of sound data flowing to and from the devices. The real-time mixing and amplitude scaling features of the new driver are brought out to the programmer through these objects. This paper describes the new objects and provides a short code example.
Mike T. Minnick,
"Object-oriented interface to the NeXT sound driver", Proc. SPIE 1785, Enabling Technologies for High-Bandwidth Applications, (20 January 1993); doi: 10.1117/12.139266; https://doi.org/10.1117/12.139266