1. i know what drop d tuning is, its when you tune the E string to D(on 4 string) butwhats the purpose of this for one? 2. WHat do you tune all the other higher strings too?
The other strings stay the same, I think it's used to make it easier to play along to guitar power chords.
It's used to be able to play a low D on a 4 string. You can get a Hipshot Xtender Key that replaces your tuning peg, you just flip a lever and you have low D, flip it back and you have E again. I used to put them on all my 4 string basses, but I play 5 strings these days. I still have one of the Hipshots here, it's a black Gotoh style tuner if you're interested PM me. Chris A.
Its more a guitar thing. It lets the guitarist play open fifths ("power chords") as a simple bar. Of course if the guitar does it the bass has to follow along, or use a 5 to grab those low Ds.
Also, because your tuning your 3rd and 4th strings in 5ths you can play voicings in a celloesqueness without retuning your whole bass to 5ths.
