To me, 2 things come to mind:
1. How do you want your snare to sound? If you want to be able to tune it high, then I'go for the 13". On the other hand, if you want to be able to tune it lower for that fat sound, then I'd go with the 14".
2. Of the 2, which one makes you go, "Wow!" when you look at it?
You'll get plenty of thoughts here, but in the end, the choice will be yours.
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