Here’s the command line for converting a WAV file to raw PCM. If your distribution provides Libav instead, replace
ffmpeg -i file.wav -f s16be -ar 8000 -acodec pcm_s16be file.raw
s16be indicates that the output format is signed 16-bit big-endian. The audio rate is changed to 8000 Hz.
You can import and play raw PCM using Audacity.