Can anyone please tell me what wood is this?
 

I would really appreciate your help, thanks!

Which piece? I'm seeing mahogany, maple, walnut and purpleheart

Which of the woods are you talking about, the wider or narrower piece? I'm guessing the color is not accurately shown, and the image is a touch grainy, but I'd guess the thicker piece is alder. Won't even hazard a guess as to the thinner piece.

I'm sorry I forgot to specify, I would like to identify all of the woods composing the bass: Body, back, neck, is this a 5 piece neck? Thanks!

This would be easier if we knew the make/model of the bass. Then we could just look it up. I'm with the first reply, though. Mahogany, Walnut, Maple, Purpleheart.

The neck looks like flamed maple and purpleheart as bassteban said.

I tried to to look up the model, but the luthier doesn't have a website or contact info. Seems to be one of a kind bass...

I currently don't have an amp because this is my first bass after 4 years of not playing, what would be the tonal characteristics of this bass? It's got EMG 45P and 45J pickups.

My guess is Koa wood over Mohogany, Maple neck with Purple Heart stringers.

I am not sure it's Koa, because seems to be darker.

I would just post the name of the bass. Odd are SOMEBODY here at TB not only knows the builder, but probably had lunch with him on the day this bass was finished. You can't slide much past this crowd.