I once forgot to put my ears on when I shot my heavy loaded Encore 45/70, and was surprised that it didn't blow my ears out. Much less noise then a normal pistol.

Of course they are loud, but not any louder then a large bore revolver. In fact the .357 mag is worse then a .44 or many rifle calibers. I have no problem with a few shots on game but need ear protection with any gun for target shooting. I would not get any hunting gun with a muzzle break because it will really hurt and ear protection while hunting makes it hard to hear animals unless you have the electronic muffs. I shoot the 45-70 and .475 Linebaugh revolvers with 300 to 450 gr boolits with no recoil or noise problems while hunting. Why would I want a muzzle brake that would blow out my ears?
I can't explain it but one shot at a paper target without muffs will really hurt my ears, while several shots at deer does not faze me at all and does not even make my ears ring.
Wear hearing protection at all times when target shooting and if the blast bothers you while hunting, get the electronic protection. There are NO quiet hunting guns.

The higher pressured rounds such as the .308 and .243 are going to be loud. They will be even louder with a muzzle break. I have found from personal experience, that rifle calibers shot out of a Contender are not so bad. I believe this is mainly due to the pressure limits on the firearm. I have an XP in .35 Rem and when it is really loaded up, it is a pain to the ears. Loaded to "Contender" levels it is quite tolerable.

Try to shoot a few and find out for yourself.

They are especially loud if factory rifle ammo is used in the short (even 14") handgun barrels. The slower powder means you are burning a bunch of it after the bullet is gone, resulting in one heck of a muzzle blast.
I have intentionally done this by using BL-C2 in my Contender 35Rem when shooting silhouette. It is fun to shoot along about dusk. It produces a prodigeous flame and all the leaves rise up for about 3 feet in front of me.
Using more suitable powders (I use H-322) reduces this somewhat. They will still get attention, though.

Elsdude,
You will get more blast/noise with the shorter barrels but i don't find it excessive with 14-15" barrels. 10" barrel are noticibly worse with factory ammo. If you reload try extruded powder as i've found ball powder has more blast/noise.