The above demo applet will generate some short tones:
- type 2-9 to get the corresponding major interval 2nd to 9th
- type m to get the milliwatt tone (at 0 dB)
You may need to click in the applet's area to get its attention to key strokes.

The above very simple applet demonstrates how I've used the sun.audio.* classes in the JavaTuner applet and includes mu-law conversion code. The Java source code, with many comments, is available to anyone who wishes to browse it.