#1
This might be a derp question, but whatever.

I've been tuning down my bass (4-string) for the band that I'm in now, and I realized that now I'm tuned to BEAD like the first four strings on a 5-string tuned to standard. Tuning that low obviously makes my strings a little more loose than I'd like. If I got a 5-string set of strings and just put the first 4 on and tuned them to BEAD, would that gauge of string put too much tension on my neck, considering it was built for a 4 string?

Might be an obvious answer, but I don't wanna risk damaging my guitar.
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#2
The truss rod would need adjustment, but don't worry, you won't damage the neck.

You probably have to resize your nut slots to accomodate the thicker strings though. That would probably be the trickiest part.
#3
Should be completely fine. You'll need to reset your action/intonation/truss rod, and file the nut, but that's nothing uncommon. If you're new to such drastic changes, just take it to a shop and ask them to set it up for a 5 string set and they'll likely be able to do that no problem

Good luck!
#4
The heavier strings won't damage anything because you are tuning them lower.

You may not even need to adjust your truss rod. I would guess that the tension of the heavier strings in lower tuning pretty much matches the tension of the normal gauge strings in standard (maybe not exactly, though so some truss rod adjustment may be needed). Also, heavy strings may not fit your nut
Quote by AlanHB
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#5
I would not recommend doing that, but I realize that some bassists do employ that method (and a few guitarists - notably Keith Richards of The Rolling Stones). The missing string creates an empty space on your fretboard that can screw with your playing. Take a look at some strings that are specifically designed for down-tunings, like the DR DDT.
"Maybe this world is another planet's hell?" - Aldous Huxley
#6
You are likely to get rattle and fret buzz if you down tune normal strings E to B.
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