Instruments and Devices

Tao provides a set of classes for creating primitive acoustic building blocks. These are derived from a generic Instrument class and include String, Rectangle, Circle, Ellipse and Triangle . The String class creates a single line of cells and springs whilst the other classes create 2-D sheets of material in a variety of shapes. Using these instrument classes you don't need to worry about creating the individual cells or springs which link them together as this is taken care of for you.

It should be mentioned here that in the rest of this document the generic term instrument is used to refer both to these simple building blocks and also more complex arrangements in which several pieces of material are coupled together. In the latter case the term compound instrument is used.

A number of other classes derived from a common Device class are also provided. Devices are objects which:

• allow the primitive instruments listed above to be coupled together into more interesting compound instruments;
• provide the means for applying external excitations to the instruments;
• enable sound output to be generated by `listening' to points on instruments, writing the resulting time varying waveforms to sound files.

Devices which are available in the current version of Tao include bows, hammers, connectors, stops and outputs. The purpose of each of each type of device is explained in the following sections. But before moving on another fundamental object class needs to be introduced - the access point. Whenever a device interacts with an instrument in some way an access point is involved. You don't need to worry too much about how to use them at the moment but they are described later on in section *.