That, my friend, is the story of generators in a nutshell. Cheap ones are noisy. Sometimes expensive ones are not. I was wandering thru an outdoor art show last year and one of the artists was running a 3300 watt generator that was the quietest I've ever heard. It was a brand I've never heard of and I was unable to find on Google. He said he'd paid a little over $1100 for it online somewhere. Good luck finding one.
In the meantime I give you these words of wisdom: you always pay for what you get; sometimes you even get what you pay for.