I have made a couple of 2016 plates in B by using solder. Use silver solder if you don't want lead poisoning and a very small soldering iron. Not that hard. You can easily go as much as a diminished 5th down. This changes some of the response for the better and some for the worse. Solder a few old plates first to get the hang.
Tuning up a step is no problem by removing material. If you gash a reed, sand the whole thing to remove the gash if it's not too deep. I just use a jewelry file and then sand off the burrs.
This brings me to another issue which I tried to change at Hohner 25 years ago. I said why do grind the reeds across the reed instead of down the reed. This would eliminate a great deal of metal fatigue. also why not test the reed lenght and weight and size for optimum response at that pitch, On the chromatic the high B and C# have always been stiff, yet if you tune a set of plates down a half step those same pitches play fine on different size reeds.
An optimum reed set up might look very weird in its varying lengths and sizes, but nobody looks inside the harmonica when you play it. 25 years ago the guy at Hohner told me we would need a third World War to get the factory to change making reeds in a uniform size going from big to small on the way up the harmonica. I pointed out that the C# in hole 4 is longer than the C in hole 5 and he said that was his point, the reeds get shorter as you go up the harmonica regardless of pitch.
We generally cover all this stuff at the Seminars like the one at the Grand Canyon.
Harmonically yours,
Robert Bonfiglio http://www.robertbonfiglio.com
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