my son was about 5 weeks old at my sister in laws wedding and reception - what we did that seemed work - and didnt seem to bother him - we took the stroller right into the reception - then with the stroller being around him it seemed to block out some of the noise - make sense? we also tried to keep him away from the noise as much as we could (well away from the speakers)
but i will forewarn you that everyone and their brother is gonna wanna hold her - so if you arent ready for that then you may not want to bring her. The noise didnt bother my son at all really - and neither did being held -and on a good note with being held usually people hold them in the traditional baby hold (swaddling like) and that shields the ears too - or up on the shoulder and one ear will be covered then too -
you will be fine! hope the info helped!
S. w.