We used to have an open station IH 444 then went to a cabbed tractor (with crappy radio or was it the speakers problem??), now back to open station IH 1066.
Throughout this entire process, I've always used in-ear monitors plugged into my Ipod so I can bring as much variety as I care to...(no radio though of course)
Then I wear some muffling over-ear muffs to tone all the noise down and it's been fantastic. I can't comprehend 'not' using the IEM's with over-ear protection on. The IEM's alone will attenuate much of the outside noise, add the over-ear muffs and it changes your world.
Since I put the Ipod in my pocket, connecting wire under my shirt, it's not dangling around trying to get caught on things and I can move around freely.
I don't know how loud all these tractors are. The 1066 with straight pipe can make some noise when you're at PTO speeds cutting a field so the extra quiet of all the stuff plugged into the ears is very nice.
Sounds (Ha, no pun intended) that you've gotten it figured out so I'm just adding my comments for a casual reader who's wondering about their options.
Years ago, I had a pair of noise cancelling ear muffs that would however, let the voice frequency through (so I could literally hear my wife BETTER with them on while engine is running than with them off.....she never understood that and it always irked her that I'd leave them on while talking to her heh)
Anyway, they finally blew up and were several hundred to replace and that's when I went to the IEM + over ear as the over-ear muffs aren't expensive at all.