Boomerweps wrote:
Studies have shown that it generally takes +10dB to be perceived as twice as loud (psycho-acoustics). For most, it takes a +6dB change for people to easily notice a loudness difference.
Spent my career in sound and can
easily detect a 3 db difference. ;) Regardless, the point is the open frame genset the OP has selected has a synchronous motor that runs at a constant (and teeth rattling) speed of 3600 rpm
regardless of load so it's
always noisy. :M An inverter genset will be dramatically quieter not only because of better baffling due to the case design but more often than not will be running much lower than it's max speed, thereby dramatically reducing noise.