Tongue blocking mouth feeling
I haven't had problems with diatonics but tongue blocking while using the chromatic is different.
A 4 holes embouchure only cover three holes in the chromatic and I have to change my mouth feelings in order to achieve a four holes embouchure.
I put this post in General because I think is better for recalling answers from David, WInslow or forum members.
When I play diatonic (tongue blocking) the note I play is aimed slightly at the right from my mouth center.
When I play chromatic I need to aim the hole more lateral, almost with my right canine (If i don't switch the tongue), in order to obtain a fourth hole embouchure.
Do you have any feelings about aiming the hole you have to play?
Like, Hank, I haven't in the past focused on where my right-side embouchure opening is in relation to my teeth - it's just "wherever the right corner is on the harmonica itself."
But if I try tongue blocking a single note in the right corner on a diatonic and then switch to a chromatic, I notice that the location of the opening shifts to the right a bit. Both openings are somewhere in the vicinity of the right eyetooth (canine). On chromatic, the opening shifts slightly to the right, but not by much, maybe 3mm or so.
If I widen ny tongue block on chromatic, I open my mouth wider and the opening moves farther to the right. it's like the opening and the harmonica are riding together, sitting in the same seat as it rolls down a hill.
Try this experiment: Play a split, with one note in each corner of your mouth and one or more holes blocked in the middle. Start with a three-hole spread (one hole blocked).
Then, keeping the same note in your right corner, widen to a four-hole spread, moving the note on the left farther away. (the harmonica will go deeper in your mouth.
Then widen to a five-hole spread (octave), still with the same note in the right corner of your mouth. The harmonica goes even deeper.
Then return to the four and three hole spreads.
Note what happens to the location of the right corner relative to your teeth.
But also note your experience with the harmonica and with your lips and jaw.
To be really thorough, try this experiment while holding a note steady in the left corner of your mouth.
Never thought about where I aim - I know with the chromatic it is a really big/wide 'smile' and I just go for the sound of when the note is clear and definite. I don't think I want to start thinking about 'aiming'! I just listen and adjust until it's what I want. Maybe not the answer you were looking for but I just thought I'd share what I've experienced.