We have a lot of mis information about the Champion generators on here.
It is disingenuous to say how loud the Champion contractor generator is, then compare the decible rating to a Honda ibverter. If you fairly compare a contractor style Honda to a contractor style Champion, you will find them comparable.
Likewise, the Champion inverter are very similar noise wise to Honda's inverters.
And finally, the Champion inverter vary the rpm with load just like a Honda or Yamaha inverter.
It is NOT like if you plug a lamp into a Champion inverter, it will run at full rpm.