- CompressInputStream :
Converts a PCM byte stream into an A-Law or u-Law byte stream. 
- DecompressInputStream :
Converts an A-Law or u-Law byte stream into a PCM byte stream. 
- ConvertInputStream :
Converts an A-Law into u-Law byte stream or vice versa. 
- WaveOutputFile :
Writes sound data into a wav file.
- EavesdropInputStream :
Acts as an FilterInputStream, but takes as well the audio input stream and sends it to the default audio output device (i.e. speaker).
- SoundPlayer :
A component that will play a given sound file and has simple control buttons like start, pause, rewind.
The PCM-Format is :
 Willi-Hans Steeb; Mathematical Tools in Signal Processing with C++ and Java Simulations; International School for Scientific Computing
Java package that offers a virtual mixer that provides multiple speaker and microphone lines.