I'm a tuba player who's struggling to get above the 2nd E above middle C, would a bigger mouthpiece help with this at all?

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*2nd E above middle C on the trumpet. Bought one a few months ago, and still struggling

no a bigger mouth piece would not help. I my self am a tuba player and you really wouldnt be able to fit a bigger mouthpiece on. I am using a Bach 7C mouthpiece. and its does just fine