Thanks for all the suggestions. I was able to get it working with unpack. The header occupies bytes 0-46 of the file and from there

read IN,$buffer,2;
$value = unpack('s',$buffer);
[download]

enclosed in a suitable loop yields the data values (for a 16-bit file).

I never was able to find Audio-Wav on Activestate. When I search using keyword "Audio" on Komodo/VPM, it doesn't show up. I tried the same thing with command line PPM and got same result. There is Audio-(Daemon, FLAC, Play-MPG123, PSID, Radio-V4L, SID, Tools, WMA) but no Wav.

Anyway, reading it as above is pretty straighforward so mission accomplished.