Ok, I have a screamer. She drives me crazy because there are neighbors nearby, and she shrieks at the top of her lungs - kind of sounds like a shrieking toddler who was a heavy smoker! The noise is atrocious.
She starts short and low, then increases in length, pitch and volume. She sings along with the rooster (between his crows), but does it on her own too - no emotions about it. I am afraid I will need to put her in the garage to sleep every night - the rooster's crows are loud but soothing and musical. Her screams are anything but, particularly at 6 a.m.
She was hatched with slight defects, and I have wondered if her singing - she is clearly singing to herself - is another result of what I hypothesize is slight brain injury. She kind of spaces out and doesn't really grasp that I am yelling at her trying to train her to shut up. She didn't do this until she began laying, and held off for several months after an egg-binding incident nearly did her in - my guess is it took that long to heal internally and her body wasn't up to the exertion.