1. First and foremost, there can't be any knots, wormholes, cracks, rotted parts, twists or anything that interferes with the wood being a nice straight grain.
2. You need a nice straight grain. If the grain isn't straight it puts pressure in the wrong places, and is vulnerable to cracking and spliting.
3. Is the wood cut the right way? It is quartersawn, or sawed some other way. Depending on what it's being used for it needs to be cut a certain way.
4. Is this piece of wood the right size? Due to the thining of old growth forests, it can be hard to get the correct size of wood. It can be very hard to find a piece of spruce for a one piece top. And if you're building a stand up (double) bass, trying to find spruce big enough for a 2 piece top is very difficult.
5. Now that you've found the perfect piece of wood, there is one thing left to do. Check and see if it sounds good. For those that don't know, you can tone-tap a piece of wood to see if it rings well. You'll find that not all pretty pieces sound well, and some disfigured pieces have great tone.
So now that I've written all that, the question is, what's the purpose of it, and where's the destruction for mahogany? Well here it is:
If you look in the pictures section you can see the mahogany boards that I used for the sides of the electric cello. Now mahogany costs a lot, and I went through the pile to find the perfect boards. So when you look at the "after" pictures of the sides you see that I had to do some serious cutting. My best guess is that I ended up wasting 75% of the mahogany boards. All to cut out the sides.
So the main point is, here I spend all this money, time, and effort to find the perfect boards, and then I don't use 75% of it. That's a lot of destruction. Well, now I've got the pieces of wood in a box. I'll see if I can use it in some project. If not, I'll give it to my Uncle Wallace. He does some serious wittling with his pocket knife. He's really, really good at it. Since he's in West Virginia he doesn't see much mahogany. I think he can do something neat with it. He's really good at wittling old fashioned wooden cars.
Speaking of destruction, mahogany is actually a poisonous wood. When cutting it you should really use a dust collector, goggles, and dust mask. I still end up getting the wood dust up my nose, and in my eyes. It makes me sneeze for hours on end, and burns my eyes. It's some really nasty stuff. But dang'it if it doesn't make some really nice musical instruments.
Oh, and my finger is still healing from where it was caught in the machine gear. Most of the scabs are gone, but there are still two spots where there is dried blood under the skin.