Clearly not all four cycle generators are not the same and just as clearly, not all two cycle generators are not the same.There are very noisy ones and quiet ones in both applications...
Honda 2K four cycle gen-59db
1250 Watt 2-Cycle Generator GEN1250-60 db
As I said earlier,this two cycle generator is just slightly louder than my Honda 2K inverter.
Evidently some of the two cycle generators are very noisy as are some of the four cycle,as most have posted but not all of them.This particular two cycle is quieter than the majority of four cycle generators and less than the price of one RV battery.