Chabad
Quote:The singing voice of a woman is considered sensual and possibly stimulating to males. It is therefore forbidden for a man to hear a woman other than his immediate family sing and it is prohibited to pray or study Torah in that environment.
Several halachic (Jewish law) authorities are of the opinion that a recording or a radio transmitted singing voice of a woman who one does not personally know would not be actually prohibited. It is the custom however in most orthodox circles for men to refrain from hearing a woman sing in any format through any medium.
"Never trust a fox. Looks like a dog, behaves like a cat."
~ Erin Hunter
~ Erin Hunter