I'm getting a 5 string bass soon in the mail. I'm completely new to bass (I've been playing guitar for almost 2 years now). I was wondering this question earlier though. If I'm playing songs that are made for 4 strings, would the 5th string on top get in the way easily?
not really, you can rest your thumb on the B string or if you want a fatter sound, play some of the parts for the E string on the higher frets on the B.

So it will only get in the way if you let it.
GAS List:
Yes you can play em with 5 string... And sometimes even 1 octave lower
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