Question: I find that music really relaxes me and find it very difficult not to listen to music during the omer. Can I listen to acapella music?
Answer: While there is no mention in the Shulchan Aruch of the prohibition on listening to music during the Sefira, the Magen Avraham (493:1) writes clearly that one mustn’t dance during this time. As music and dancing are often synonymous, R’ Moshe Feinstein writes (Igros Moshe YD 2:137) that it has become the prevalent minhag to refrain from listening. The Aruch Hashulchan, too, writes (OC 493:2) that while engagement parties are permitted, there must be no musical accompaniment.
R’ Yitzchak Yaakov Weiss (Minchas Yitzchak 1:111) brings sources to demonstrate that refraining from listening to music is not a new minhag.
R’ Eliezer Waldenberg (Tzitz Eliezer 15:33) discusses whether recorded music is banned, too, and concludes that there is no difference between live and recorded music (See Yechave Daas 6:34).
R’ Belsky holds that one who usually listens to music when they workout may do so, as this music is not considered regular enjoyment. Certainly, one who teaches, studies or plays music for their livelihood may continue to do so.
R’ Shlomo Zalman Auerbach (Halichos Shlomo, Sefiras Haomer 11:n14) writes that one who will become overly upset without music may listen to recordings. One need not prevent one’s young children from listening, either. Others have permitted listening while driving if it helps to keep them alert.While some (Shevet Halevi 8:127) even prohibit listening to acapella music, most authorities allow such ‘music’.