Hi Leo, I see from another post you are new to the sax and although I am no expert I wonder if a 3 or 4 size reed might be too stiff for a 6 Otto. Have you tried a 2 or 2.5 as yet. I have a very similar situation and tried the Select reeds with no luck. Getting nice results from a 2.5 Royal on an OTTO 6*. As you will read here and elsewhere there is no one rule for all and will require lots of trial an error (and some cash) to find a comfortable setup that works for you. Good luck.
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