So I have a question. I understand most everything in the thread, and I've gone through it several times, taking detailed notes for the times I don't have internet, but when I attempted to master some of my tunes for the hell of it, raising the volume to where the highest peak is around -3 overcooks the sound, and it just sounds like shit. At first I thought it was my mixes, but I've gone over them a few times, and I'm beginning to wonder if it's because I'm using 16 bit (I don't have the money to shell out for a new soundcard, and I have to replace my headphones.)
So could anyone help me out? If I was using 24 bits I wouldn't have problems with my mixes being too quiet since I would have more room to work with, right? But since I am limited, how can I get my mixes loud enough to not peak too high, but not sound like shit when I raise the volume when I master them? I know it can be done, but how? If this question isn't relevant (most everyone here is probably never going to be using 16 bit) then I can ask elsewhere.
Edit: the "overcooking" I was hearing was being caused by a short in my headphone's wire somehow

but for the sake of knowledge, what would help me have louder masters that sound good? Surely there must be something I can do to get a bit more volume. They just sound too quiet, even loud. Am I really loosing that much quality when I export my mixes?