Hearing protection is a much cheaper option...
My 2005 4520 is pretty noisy at PTO RPM (2400). This tractor has the Deere Powertech engine, not the Yanmar of the later models. Good engine...more cold natured then a Yanmar, but more lower end torque. Yanmar engines are great though!
Anyway, when I'm mowing (flail mower), I have sound attenuator muffs on. Wintertime snow blowing...I normally have a hat with muffs or a hood which reduces the noise quite a bit