You’d think I get that question a lot, but actually I don’t – most people pronounce it a certain way and are absolutely, positively, sure they’re right. There are so many pronunciations it’s incredible, so who am I to choose the “proper” אחד? Let ’em pronounce it however they like, I say.
That being said, the number of pronunciations I hear is borderline ridiculous. Here are the most common ones I’ve heard.