i’m inclined to agree that the labelling is on the ‘high side’ - if i understand correctly, the midi spec stipulates A440 is note 69, middle C would be 60 then, by that ref - on the AFour when I play Midi note 60, i get C5 displayed … now a couple of standards exist for labelling but I think that may be higher still - my reckoning is that it is only labelling and they may adopt using that system for the following reason …
The NOT param displays a range from C 0 to G 1 where G 1 in this case is G 10, there’s just no room - so in order for Elektron to display the octave ranges with a negative label and a sharp, they’d need more characters than they have, so i think it’s just a labelling solution they’ve adopted, whether it fits with the accepted standard i’m not sure but starting from C 0 seems logical to me
One man’s C3 is another man’s C4 ! according to Wikipedia middle C is most commonly accepted as being labelled C4, so it echoes your point !