walnut neck thru?
 

What would it sound like?

Not enough info - there's even a considerable difference in density (just one of the factors that affects tone) between the different species of walnut. Claro and European walnut are less dense than American Black walnut or maple, which usually would mean lighter weight, brighter more resonant tone... emphasis on 'usually'.
That said, I have a walnut and maple laminated neckhrough thunderbird and it sounds dark and punchy. Lots of sustain, not a lot of resonance.

How about a mahogany neck thru? With barts and a pre?

I love mahogany but not for a full build. Neck through is fine IMO however, I would do a Maple top or even maple wings. If you are going for the mahogany look through out, you might consider Swamp Ash sides and a Mahogany top.

However, with that said, using a pre-amp will negate most of the tone charecter of the wood.

how do you think the mahog neck thru would sound?
also any tips on a finish process for the mahog? i am a tru-oil fan so i think the best way to go is to take care of the mahogany and maple seperately, then apply finishing oil coats when glued up.
Thoughts?

mahogany is going to be darker tone them walnut. Also lighter weight. My understanding of walnut is its not as bright sounding as maple but ussually allmost as heavy weight wise.

Gibson thunderbirds have a mahogany neckthrough, you could see if there are any clips of a thunderbird with barts to get an idea of how it could sound.

With that combination, you run a greater risk of the instrument sounding dark & muddy - all other things considered, of course.

That's why some maple, or some swamp ash, or at least some walnut or wenge is usually a part of the recipe as well... :hmm:

MM

If you are going to finish with tru-oil I would just just wipe on and wipe off. Use 000 steel wool between coats to keep things nice and smooth. make sure you wipe clean with mineral spirits. There are several ways to finish it off depending on if you want to fill the grain or not. If you want the grain filled, I would use Belham's grain filler. I like to use my fingers to get the filler in all the nooks and cranies, plus it allows you to get it only where you want it. Make sure you use a squeegie to get it off and then completely sand with 320 grit. Then start your oil applications. I thin the oil with mineral spirits 50/50 for about 4 coats followed by 2 to 4 coats of my home brew oil/poly blend (like Sam Maloof's) Then, if you just want a low luster finish, you can apply wax with 0000 steel wool and rub in and wipe off. Or if you want a high luster finish you can apply 2 to 4 coats of straight wipe on poly. For best results wet sand, buff and polish. If you want a glass like finish that is. If not, wax on, wax off after oil/poly.

Good luck.

Cheers.

Best guess - they will all sound like basses.

Aesthetically, I think walnut is gorgeous.

Ergonomically, it'll be heavy as stink.

IME, walnut wings with maple neck gives a very woody percussive sound, kind of like wood blocks. Noticeably tighter than ash or alder.

Walnut in the neck of a neck through produces what some refer to as a compressed effect, almost like wenge. Think Warwick Thumb, but a little brighter and you will get the idea.

Mahogany + Barts is a recipe for mud.

Right now I've changed my mind to solid maple with barts......to bright? I'm looking for a good full balance while still being articulate

Sounds like my Pedulla MVP - an awesome bass and certainly not "too bright".

I love the look and sound of MVP's but I worry that therr tone has more to do with the pre than their wood....I love their clarity

My suggestion: Leave the gun... take the CANNOLI!