- Peninei Halakha
Some authorities maintain that just as one may not listen to live music during the Three Weeks, so too one may not listen to recorded music played on home electronic devices during this period. One may listen only to songs without instrumental accompaniment during the omer period and the Three Weeks. This is how some of the greatest poskim rule (Igrot Moshe yd 2:137; Yeĥaveh Da’at 6:34). Some poskim even forbid listening to non-instrumental ("a cappella") music during these periods (Tzitz Eliezer 15:33).
However, some permit listening to music on electronic devices, reasoning that the Aĥaronim only prohibited listening to live musical performances, which entails some degree of festivity. Listening to music through electronic devices, on the other hand, is not particularly festive. Granted, when phonographs, radios, and tape recorders were first introduced, people truly experienced joy when using them to listen to music. Today, however, when everyone listens to music on electronic devices all the time, people do not experience so much joy in doing so. Thus, it is not prohibited to listen to them during the Three Weeks.
Furthermore, a distinction can be made between happy songs and regular songs. It is only fitting to prohibit happy songs during the Three Weeks, whereas regular tunes, and certainly sad ones, should not be prohibited. Similarly, the Gemara (Shabbat 151a) teaches that the custom was to play flutes at a funeral in order to arouse people to cry out in anguish over the deceased, and this was part of the mitzva of accompanying the deceased to his final resting place (levayat ha-met). This shows that there is no sweeping prohibition against hearing instrumental music. Rather, one may not listen to happy tunes during times of mourning. I heard from my father and teacher that not only may one play sad instrumental songs related to the destruction of the Temple on the radio during the Nine Days, but it is actually good to do so, because it inspires people to mourn the destruction even more.
 Among those who prohibit listening to music on the radio are: Igrot Moshe, yd 2:137 and oĥ 1:166, which tends toward stringency with respect to listening to instrumental music at all times nowadays; Yeĥaveh Da’at 6:34 permits listening to instrumental music in general but forbids listening to them on the radio and the like during the omer period and the Three Weeks. (In private conversation, however, he allowed Israeli radio station Arutz Sheva to play music during these periods, to avoid causing them to cancel their Torah-oriented segments.) Tzitz Eliezer 15:33 even forbids listening to non-instrumental music on the radio during these mournful periods. However, the rationale of those who rule leniently is strong, especially since the entire custom of refraining from listening to instrumental music and dancing during these times is first mentioned in the works of the Aĥaronim; it is not an ancient institution. Similarly, Responsa Ĥelkat Yaakov 1:62 concludes that listening to music on an electronic device is not included in the decree (or the custom of mourning) because these devices did not exist when the decree was first enacted. It seems, then, that the prohibition depends on whether or not the music is joyous. We can also derive this from the fact that the Aĥaronim permit attending music lessons during these periods because such music is not joyous. Clearly, then, it all depends on whether the music is joyous. Maharam Schick, yd 368, distinguishes between joyous music and sad music, ruling that sad music is not forbidden during times of mourning. This can also be inferred from the wording of Rambam in Laws of Fasts 5:14, where he discusses the prohibition of playing music after the destruction of the Temple: "Similarly, they ordained that one should not play melodies with any sort of musical instrument. It is forbidden to celebrate with such instruments or to listen to them being played, [as an expression of mourning] for the destruction [of the Temple]." According to this, it appears that the prohibition relates mainly to listening to joyous music, which is associated with dancing, while regular songs, and certainly sad ones, are permissible. Some people do not make any distinction between joyous songs and sad songs. These people take care, on the one hand, not to hear or play musical instruments during the Three Weeks or the omer period, but on the other hand will play joyous non-instrumental songs. They are mistaken, however, as one should be more stringent about hearing happy songs, even without instrumental accompaniment, than about hearing sad songs with instrumental accompaniment, concerning which one may rely on the lenient opinion. See R. Shmuel David’s article in Teĥumin 13. Also see above 3:10.
Even according to the more stringent opinion, one who is listening to a radio talk show that occasionally plays musical selections is not obligated to turn the radio off. However, one who takes care to turn it off when the music comes on should be commended (Hilkhot Ĥagim 25:9).
It seems that even according to the more stringent poskim, one may be lenient on Friday afternoon and Saturday night, because the sanctity and joy of Shabbat extends to these times. Indeed, we do not say Taĥanun on Friday afternoons, and we continue to wear Shabbat clothing on Motza’ei Shabbat.