In my experience, in most contexts "a few" would be 3-9.
For example, I am going on a picnic with a couple of friends:
"Shall I bring a few bananas?"
If I were bringing 2 bananas I wouldn't say "a few" - I'd say "a couple, (though "a couple" might, in this context actually be 2 or 3, (or maybe even 4, especially if I really like bananas!)
If I were bringing 10+ bananas (i.e.double figures), I'd say, "Shall I bring some bananas", or I'll bring a load of bananas.