Growing up, my dad had a 2-stroke Mariner 30. It rattled like nobody's business, but when fish would school, they would stay up if we kept the motor running. If we turned it off, they would go back down 9 times out of 10. I now have a Honda 4-stroke. I troll for stripers and have tremendous success. I also use live bait and anchor lock over schools of hybrids/stripers. Sometimes schools are active and sometimes they are not. As I am graphing, i use my big motor to maneuver the boat and when I find a school, I engage my autopilot. I never shut the motor off until I catch a fish. I think sudden noises spook them more than consistent.

I told my fishing partner that rather then buy or build a thumper we just need to put an amp and subwoofer on the stereo