These are probably the easiest to tune. You see a couple of small posts at the barrel end of the sound board. Now take the notches on the reed and place them over the posts. Make sure the reed will sit down in the tone channel toward the mouth and and then set the wedge right up against the posts on the sound board. Slide the 'guts' into the barrel keeping your thumb over the end of the reed so it doesn't move around until it stops, about a 16th of an inch or so. Then blow, you're done.
There is a post somewhere on doing this, I will try and find it unless someone else here knows where it is.
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