Question: When one hears a beracha being recited over the radio or telephone, can/should he answer amen Can he be yotzei a beracha in this way?
Answer: In order for one to be yotzei with a beracha he hears, it must come from a person who is obligated in the mitzva (Rosh Hashanah 29a). Even in order to answer amen, he must hear the beracha from a person whose beracha is meaningful (see Shulchan Aruch, Orach Chayim 215:3 regarding a small child’s beracha). Therefore, all agree that one is not yotzei and does not answer amen to that which he hears on a recording, when no one is actually speaking. Almost all poskim agree that one cannot fulfill the mitzvah of hearing shofar via microphone, telephone or radio, because one must hear the authentic sound of a shofar (Rosh Hashanah 27b). The ruling regarding megillah reading via microphone is not as clear. Although one does not hear the actual voice of a valid ba’al koreh, but a device-generated reproduction, it is better than a recording in two ways. First, the sound is produced directly based on the sound waves from the ba’al koreh. Secondly, the reproduction is heard at essentially the same time the ba’al koreh reads. Therefore, although most poskim believe one cannot fulfill the mitzvah via microphone, the lenient position is marginally tenable (see Tzitz Eliezer VIII, 11; Igrot Moshe (OC II, 108) leans toward permitting it, but he appears to be based on a lack of related scientific information.) The gemara (Sukka 51b) minimizes the importance of hearing the voice of the person reciting, if one knows what is being said. It tells of a huge structure in Alexandria, where flags were waved to inform people when to answer amen. However, Tosafot (ad loc.) limits this precedent to cases where participants were not attempting to fulfill any mitzvah at the time. On the other hand, it does seem to indicate that one can answer amen without hearing the voice in a case where one knows what beracha it is and is not obligated to be yotzei (see Shulchan Aruch and Rama, OC 124:8).
Rav Shlomo Zalman Auerbach (Minchat Shlomo I, 9), while agreeing that one can answer amen to that which he hears in shul via microphone, disagrees regarding radio and telephone. The distinction is that the people in Alexandria were close enough to be connected to the berachot without hearing them. However, there is no physical connection between the person reciting and the one “listening” at a distance via telecommunication. One can raise the following counter argument to Rav Auerbach’s claim (which is based on logic, not sources). Even though, scientifically, the reproduced voice is new and is not the transfer of the original voice, the immediacy and realistic reproduction creates a palpable connection even over great distances. Although to be yotzei with someone one likely requires hearing the original sound emanating from the valid halachic entity, we learn from Alexandria that this is unnecessary in order to answer amen; a feeling of connection may suffice. Indeed, Rav Ovadia Yosef paskens that one cannot be yotzei via telephone but can answer amen and answer along with prayers that require a minyan (Yechave Da’at II, 68). Another factor which might preclude answering amen is the possibility that the voice travels over a place that is filthy or contains idol worship (see Shulchan Aruch, OC 55:20). However, there are a few reasons to be lenient here. First, it is not clear that we pasken that this is a problem, especially when there are other points of leniency (see opinions in Yechave Da’at, ibid.). Also, even if it were certain that “the voice” travels over such a place, the fact that it travels as electrical signals alone may be reason for the halacha not to apply. In conclusion, it is unclear whether one should answer amen to berachot heard via telecommunication. If one likes, he may rely on ample grounds to do so, realizing that the stakes regarding an unwarranted amen are lower than regarding berachot (see Igrot Moshe OC IV, 91). However, one need not feel halachically mandated to answer (see also Piskei Teshuvot 215:3).
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