Is it permitted to purchase a musical instrument and play it at home? I am asking because I have heard that there are opinions that say it is not allowed since after churban bais Hamikdash, we are not permitted live music unless its for a seudas mitzva/simcha?
The Gemara prohibits music after the destruction of the Temple (Gittin 7). However, as Iggros Moshe (Orach Chaim 1:166) points out, the vast majority of authorities (commentaries to Gittin 7) write that the prohibition applies only to music played in a beis hamishteh, a bar or pub, and not to music at home. Even the Rambam, who writes that all music is prohibited (Taanios 5:14), and whose words are echoed in Shulchan Aruch (Orach Chaim 560), writes the contrary in a responsum. [Elsewhere Shulchan Aruch makes specific mention of music of idolatry, implying that ordinary music is permitted.] It is therefore the common custom to be lenient with regard to musical instruments, and it is permitted to purchase an instrument and to play it at home.