Someone in my shul tends to Daven his quiet Shemona Esrei a bit too loud that i could hear him. Am I supposed to answer Amen if I hear the end of his Brachos?
According to most poskim you should not answer Amen to his brachos, because he is not supposed to be davening so loud when he is in shul.
On Rosh Hashana or Yom Kippur, when we are allowed to daven loud, if you hear someone finishing a bracha you may answer Amen to it.
R’ S.Z. Auerbach zt”l in Mivakshei Torah sivan 5755 Siman 163,Shevet Haleviu 3- 15(a). Elef Hamagen 582-43. Eishei Yisroel chap 4 ftnt 12.