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 (recorded music), 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 (redemption 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 may certainly act leniently 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, one may continue to play music until the week during which Tisha Be’av falls out. 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 act stringently regarding this matter beginning from Rosh Chodesh Av. Just as music teachers may act leniently 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 Daycare programs which operate during the “Three Weeks” and play songs with musical accompaniment as part of their daily routines may act leniently and continue to do so during the “Three Weeks.” Maran Rabbeinu Ovadia Yosef zt”l and Hagaon Harav Yaakov Kamenetzky zt”l rule likewise.