My half Siamese had the loud meow but didn't use it to point of being a nuisance. In fact, his meow is how we learned that he was half Siamese. I had noticed that he had an unusual meow when we got him from the Humane Society at 6 weeks old. But I did not know enough about Siamese to recognize it.
He had a brown, black and gray tabby coat with a white bib and belly. Green eyes. No color points.
But, on his first vet visit, he startled the vet by protesting very loudly about having a thermometer stuck up his rump. The vet checked out his body proportions, eye shape, ears, legs, head shape, and told us that our kitten definitely had Siamese ancestry and he was certain that he was half Siamese. So was I as he grew and showef all the typical Siamese behaviors.
He meowed only at certain times, though, like when responding to us when we called him, or to get our attention when he wanted something (usually food), and to chat with me when I got home from work. We had a two way conversation for about the first 15 minutes every day. He greeted me, I asked how his day was, he answered, and I said, " Really? Tell me about it." And he did.