Okay, heres the problem: I sound really great singing when the volume is speech level or slightly louder. But I've noticed that when I try to boost my volume, I get raspy, loose range, and sound nasally. The high notes sound a little like nails on a chalkboard and I'm out of breath in places that I'm normally not at in comfortable singing voice.

Any ideas as to what's wrong, or any exercises that I can do to improve this? Or am I just singing too loudly? How loud do I need to be anyway?

Sorry that I can't provide any audio examples. It makes it difficult to try to answer this. Hopefully someone knows what I'm talking about.

wish i could help ya but i still consider myself a rookie

well i wouldnt be so concerned about your volume stick to the one where you sound best. If you perform you will probably have a mic, and then your volume isnt the thing you need to worry about.

You don't need to sing very loud. If you try too hard, you might use to much air and that will dry out your vocal cords. Pushing too hard might also create unwanted tension, make your larynx raise etc... If your voice is placed properly, it should project enough without requiring you to "try" to sing louder than necessary. Too much is like not enough. You have to find your balance.

Yeah, the problem was trying to sing amped (and not very well amped either) over a guitar and drums who were very close to me. I thought, man I sounded bad. So I went home and tried singing just as loud unplugged and determined that this was not the volume that I needed to be singing at.

Next time around, I'm taking some Hearos ear filters with me and just singing loud and comfortably enough for me to hear. Anything louder and it just all goes to pot.

Although it seems like he is singing way louder, Dio sings at speech level volume. I also heard that Jimi Jamison told JLT to let the mic do the work. It is hard when you don't have monitors and you want to be heard over the guitars. Not sure about excercises, but I know it is not a good thing to sing loudly for an extended period of time. Some people have naturally loud voices and it may work for them.

It looks like you need one of those new vocal acoustic monitors VAM:

http://thevocalacousticmonitor.com/

I haven't tried these yet but they seem pretty cool and convenient on top of it.