outlet

In order to enable and disable portions of an audio program easily, and to be able to reuse them multiple times, you will probably want to encapsulate an entire audio-generating or audio-processing procedure inside a single patch with inlets and outlets so that it can be used as a subpatch object in some other patch. This patch shows an example of a simple 2-oscillator frequency modulation tone generator that could easily be used as a subpatch in some other patch.

Using both the key and keyup objects, you can tell when a key was pressed and when it was released. The split object allows you to isolate a range of numbers; it passes only the specified range of numbers out its left outlet, and passes all other numbers out its right outlet. The numbered keys 0 to 9 correspond to ASCII codes 48 to 57, so it's easy to isolate those keys, and subtracting 48 brings those numbers down into the range 0 to 9.