compare two voices

[phil]

You didn't indicate how deep you want to get into
the code yourself.

I am gonna step way out of my mathematical depth here
and say this should not be too difficult in python.
1. you need to know the format of .wav
    surely it is a set of frequency amplitude pairs.
2. you need to know the sampling rate is the same,
     say its a hundred points per second, a five second
      speech is only a 500 hundred point pair of curves.
3. then perhaps a package like MatLAb would give you the
      curve fitting algorithms to obtain a score.
     It might even compensate for an average frequency
      diff between the two samples.

The difference in tonal quality between native Germans
and native Thais I would think would not enter into
it, because that is part of what you are testing for.

The math for comparing two waves which are different at
every point, have different base frequencies and different
rates is hellacious, but its been done.
Python would just be the wrapper, and a good one.