rowuk

I switch mouthpieces depending on horn or general style. I find it makes more sense to use a shallower mp when I need a bright sound than to try and get that sound with my "orchestral" piece. Another switch is when you play flugelhorn, the deep vee mouthpiece gives me a sound to kill for. I do not switch because of range-ever. When I am in the big band, where we are amplified, I go with the bright sound - it prints better to the mic.
I do not change "embouchures" though. My lead piece is not so shallow that I have to bend anything.
If the difference between the Shew lead and 5c is too great, then that is not the right combination. One of the two will have to go and be replaced by something better. I don't know if there is a 5D or 5E, but there is a 7D and 7E that may fit your needs. The only way to know is to try it. I have no personal experience with the Shew MPs.
I believe that the mouthpiece can be a big help depending on the types of playing that you have. It is much easier to get a slightly shallower mouthpiece to brighten up your sound instead of wasting energy trying to get dark sounding hardware brighter. If the rims are essentially the same, the switch is a piece of cake.

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