Different sneezes

Why is it that some people must sneeze loudly and deeply, while other folks are able to get by with seemingly a small nod of the head? My sneezes seem to require a very strong expulsion, with an audible component. I’ve heard other similar loud sneezers. But I have also seen very gentle sneezers. I don’t think I can control that. And maybe a related question is whether sneezes are voluntary or involuntary.

As usual, I seek the wisdom of the web.

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