You can see that -2 and 3 are both G note, one is “g” and the other is “G”. But they actually sound different, Am I missing something? Can someone explain this? Should I use another key mapping for my harmonica?
(I’m so sorry, I’ve just edited the topic.)
They should not sound different because they are the same tone. This is the way that Richter tuned diatonic ten hole harps are built.
The lower line in your info sheet has lower case letters to indicate tones produced when drawing air through the indicated hole(s).
BTW the key mapping is correct.
Regards,
– Slim
Welcome to the forum @xemenis!
Are you certain you are playing clean single notes on each? If not completely clean, the tones will sound different as you are getting some tones from adjacent holes.
Again, welcome aboard. 
Hey @xemenis - welcome to the forum! So glad to have you here. The map you have I correct. Probably what you are experiencing is very common with beginner accidentally bending down the -2. This usually happens because the back of the tongue is raised in the back of the mouth like it is when we say “kk” (and/or the jaw is not dropped, which is evident if your top and bottom teeth are too close together.)
Drop your jaw in nice, relaxed “aw” vowel shape with back of tongue lowered like it does when you yawn.
Finally, don’t draw too hard. Just a nice consistent airflow does the trick.
LMK how it goes.
Aloha,
Luke
