My friend, it's good you are asking questions, but the bottom line is; parrots make noise. Some make a lot, some make less, and yes, it can be a species thing but it's also what you put into the parrot, and how you train it, both on purpose and inadvertantly. You can get a species not known for being real screamers and because you didn't read enough on how to react to screaming only teach the parrot to scream more. Or you could get one that everyone says is really loud, and it will be a quiet bird, because it just is. Our Salty is an amazon, but he doesn't do the morning and evening screamathon, and is only loud when my wife is prepping dinner. And even then it's more laughing and a lot of Amazon mumbling. So do what you are doing... read and research, and let the bird pick you, if possible. Welcome to the parrot forum.