The laws of copyright apply here. If you downloaded the music legally, you have the right to listen to it yourself. (and maybe a few friends/household members)
However, it did not give you the right to use that music for any other purpose and that includes public re-broadcasting of it. ie. on your website.
P
Hi,
Is it legal for me to play music on my website that I have downloaded from Napster *legally*? I do not plan to distribute the song on my site.

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