My Yamaha is pretty quiet, she is definitely on par with your average i/o. But it was not like that stock and bringing the noise and vibration level down took a significant amount of planning and effort. For example, my engine bay and engine hatch are insulated, the gunnels are filled in with various types of foam, all the way up to the bow, seadek all over etc. It was a significant undertaking but - it can be done.
In general, newer hulls, like my 2016 240 are not actually bad from factory and Yamaha was very smart to design and incorporate various built-in storage compartments that break up large, cavernous spaces inside the "pseudo double hull" (2-piece construction) - which is like a resonating box that amplifies noise of the drivetrain sitting above the water level on plane - it's a jet boat! So, the new boats are less loud, stock, as compared to the older ones; my 2012 190 was impossible to quiet down to any comfortable level, the only thing I hated about it.
Sea trial is advisable. These boats are different and they are not for everyone.
That said, we like our 2016 AR240 (with a ton of mods) enough I wouldn't sell it.
In fact, we are now buying another boat just to fish offshore, my current Yamaha does pretty much everything else better.
In the crowded category of trailerable, open bow sport boats these new Yamahas are very hard to beat. For one, I could not figure out what to replace mine with, lol, and I tried. Love the damn thing!
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