Well, you don't use that expression... if you're Spanish
, you use the second one if you're not talking about some specific music
Anyway, I don't know if you're asking perhaps at a shop as cyberdark o something like that. But, if this shocks you, it really shows that you don't read Spanish press or visit Spanish ebooks store. Smashwords doesn't exist. There're very, very few shops with DRM-free books.