Listening to Music during the “Three Weeks”
All forms of dancing are forbidden during the three weeks between the Seventeenth of Tammuz and the Ninth of Av, even when there is no musical accompaniment.
This applies even when the dancing conforms to the laws of modesty and holiness observed by the Jewish nation, i.e. men dancing alone and women dancing alone with a partition separating them so that they do not see each other. However, men and women dancing together is absolutely forbidden all year round.
Although during the rest of the year one may listen to music from a tape recorder, cassette, CD, and the like, especially songs with holy words that are accompanied by musical instruments, Maran Rabbeinu Ovadia Yosef zt”l writes that during the “Three Weeks,” one should refrain from doing so. Nevertheless, when it comes to a celebration of a Mitzvah, such as a wedding, Berit Milah, the festive meal of a Pidyon Haben (redeeming of the firstborn), Bar Mitzvah, or conclusion of a tractate of the Talmud, one may listen to songs composed of holy words and musical accompaniment, for as long as it is in celebration of a Mitzvah, one may act leniently regarding this matter.
Singing during the “Three Weeks”
Singing, without musical accompaniment, is permissible during this time. One can certainly be lenient regarding this matter on the Shabbatot that fall out during the “Three Weeks”; indeed, even on Tisha Be’av that falls out on Shabbat, one may sing songs in honor of Shabbat.
One Whose Livelihood Depends on Playing a Musical Instrument
If one’s job requires him to play a musical instrument for non-Jews, he may continue to play music until the week that Tisha Be’av falls out during (meaning the Sunday before Tisha Be’av, this year, 5774, on Sunday, the 7th of Av). Similarly, regarding a music teacher who teaches students to play musical instruments, such as the violin and the like, if one will incur a monetary loss by not teaching during this period, one may indeed continue to teach playing music until the Sunday before Tisha Be’av. It is preferable, nonetheless, to be stringent regarding this matter from Rosh Chodesh Av. Just as music teachers may be lenient regarding this matter, so too, a student learning to play a musical instrument may continue doing so during this period.
Playing Music in Camps
Camps or Day-Care programs which operate during the “Three Weeks” and play songs with musical accompaniment as part of their daily routines may be lenient and continue doing so during the “Three Weeks.” Maran Rabbeinu Ovadia Yosef zt”l and Hagaon Harav Yaakov Kamenetzky zt”l rule likewise.