Check out Youtube. Lots of inventive solutions there. Most involve a power-ventilated, sound insulated box. None that I saw were designed to be very portable. Some have even added automotive mufflers, but that's only half the battle; the motor makes quite a bit of its own noise.
2014 Jay Flight 28 BHBE
2015 RAM 2500 6.4L HEMI, Tradesman 4x4, 3.73
Blue Ox SwayPro (BXW 1503)
Upgraded from an REI internal frame backpack and a Eureka 1/2 dome tent!