well, it looks like dave smith's right. unless the increment of the note is equal or bigger than 37 (36+1), you can't really modify the frequency of the midi notes. appearently evo transmitts midi in regular half tones.
so if your input looks like:
first row: 37 (or everything below), 39, 41, 43, 45, 47, 49, 51
second row: 53, 55, 57, 59, 61, 63, 65, 67
(third and fourth row doesn't seem to count)
then you'll obtain a whole tone scale (remember debussy?)
i also think that an increment of 37 is corresponding to a mid-low C (i didn't checked properly, i did it just by ear)