There are different systems of naming the octaves. For instance in German system the range of oboe is from hes (ie. b flat in the octave below a middle c) to approx. g3 . Which, I agree, still doesn\'t match the chart of your samples. But since the most effective range of an oboe is cca between f1 and hes 2 (that would be F3 to Bb4 of your system) I guess the (c) of the chart could be your C3 the e flat could be Eb3 and so on.
[This message has been edited by ondrej (edited 06-20-2001).]