Ask the Rov: May one listen to the shofar with a hearing aid?
By Rabbi Chaim Hillel Raskin – Rov of Anash in Petach Tikvah
The mitzva of shofar is to actively hear the sound of the shofar as indicated in the bracha’s text, “lishmoa kol shofar.” Yet, the blowing itself is also a part of the mitzva and must be done by someone obligated in the mitzva.1
A person who is mute but not deaf is obligated, and he can blow for others as well.2 A deaf person is exempt since he can’t hear the sound, though some recommend that he blow for himself without a bracha.3 However, being exempt, he cannot blow for others.
One who is hard of hearing remains obligated to hear shofar.4 If he can only hear the shofar blasts with a hearing aid, poskim debate his status. Some argue that it’s considered to have an additional sound mixed in, and he is therefore exempt, 5while others hold he is considered able to hear and thus obligated.6
The Rebbe notes that mechanical amplifiers may be used for shofar since they are simply transferring the sound, however electric hearing aids simply replicate the shofar sound. One cannot fulfill their obligation by listening to the electronically created sound.7
In practice, one who can hear the shofar blasts without a hearing aid (by standing close to the one blowing) should do so, and he can blow for others as well. If he cannot hear at all without the hearing aid, he should not blow for others.8
If a person has a hearing aid in only one ear, some hold he fulfills his obligation with the ear that hears without an aid,9 while others hold that interfering sound is a problem, so it’s best to remove it.10
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From The Weekly Farbrengen by Merkaz Anash
The tzemach tzedek on Rosh hashono perek ches says that one who can speak but cannot hear is mechuyav midoiraisa to blow the shofar and can be moitze others and is arguing with the beis Yosef
Perek 3 Mishnah 8