I want to build an acoustic guitar but i have some questions. A) Is rosewood better than mohagany? and which is a stronger joint, bolt on or dove tails?
It's preference, really. You can find just as much evidence to the contrary for any argument arising from those choices. Generally, you would want to play some rosewood and mahogany acoustics and see which one you like best. A dove tail joint is a traditional joint, but leaves no room for simple adjustments. A bolt-on neck allows for easy removal of the neck in case of a resetting, but can be trickier to install. Your choice.