FOC has certainly helped with penetration.
I have shot heavy ash and hickory shafts also, but have moved away from them. IMO the combination of high FOC and skinny carbon shafts has increased penetration also. So much so, that I switched to three blade heads because my two blades were zipping right through deer so fast I could not really believe it. Now my three blades are zipping right through, unless I hit something hard on the offside.
As far as bow noise, a heavier arrow certainly helps. So does a properly tuned bow, properly tuned arrow, and properly constructed string.
