In early 1993 I had the privilege of working with Gina Venolia (formally Dan Venolia) of Apple’s HI (Human Interface) and Advanced Technology Group on a couple of human interface projects. The 3D mouse was at the time a “new thing” and moving an object in a three dimensional space was somewhat of a challenge. Sounds were use to “enhance the interaction” by providing audio reinforcement to actions such as touching, dragging, approaching, attaching and releasing objects. This simple use of sound help to create a “body language” grouping the individual mouse actions into a continual gesture. Another application of user interaction audio was with the T-Cubed project. A pen was used on this interface to enter text with flick gestures. Sounds were used to provide feedback for letter confirmation, pen contact, release and audio feedback to convey the accuracy of each flick gesture. Both projects had their challenges, but showed enough success to continue with researching the use of sound in the Finder and Apple’s new Appearance Manager. Over the next few years, working together with Arlo Rose, HI lead on Theme based Appearance, created Mac OS 8.5 aural interface, consisting of over 130 sounds per set and five themes, Platinum, Hi-Tech, Beach, Drawing and Gizmo. Among other discoveries on the project was the use of spatial panning of objects, variable pitch and volume. The resource was enjoyed by many hackers to create themes such as Beastie, Bowie, Star Trek and others before being removed from the system with the introduction of OS X. Below are some screenshots of the interface and a short video clip of the Appearance Themes in action.