Today I received my Generation D back from Jerry Freeman, who tweaked the thing for me. It is superb! No squeeks when Jerry tweaks!
It was so unplayable that I just threw it in the junk whistle drawer but now that Jerry has turned garbage into gold, I am a very happy with it. It is in tune, but still has a character of its own. Thanks Jerry! I think this is going to be a home business of sorts for Jerry, so if you all have whistles lying around, talk to Jerry.
I have one of his O’Freeman Improved Feadogs that he sent me in trade for building him a Groovewhistle (almost done Jerry!) and I must say that I am super impressed with it. The tone is head and shoulders above my Waltons and the breath requirements are significantly lower as well. Jerry’s tweaks are spot on… 
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Hi, Cranberry.
The prototype tweaked Feadog and Generation D whistles Celtoid and Groovehead have are the only tweaked Generation-type whistles I’ve sent out.
So far, I’ve been able to get a fairly predictable result and some really excellent whistles, but there are still some mysteries I haven’t solved yet, so it’s too labor-intensive to start offering them as a regular item.
However, I’ll keep working on them, and when I’ve got the Generation-type whistles figured out well enough to do them routinely, I’ll let everyone know.
On the other hand, I do have Sweetones down to a science, if my experience with the eight I’ve tweaked so far continues to apply in the future. Eight Sweetones tweaked, eight very satisfactory whistles. I’ll make an announcement when I get to the point where I can make them available.
Best wishes,
Jerry
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Rather than have people send whistles to me for tweaking, I’ll probably just tweak a bunch of new ones and put them up on eBay. The shipping for a Generation or Clarke whistle costs almost as much as the whistle itself.
Best wishes,
Jerry