music

Question

You wrote that the heter to listen to a capella music is totally bogus. I understand that your father shlita paskens it's asur. But to say it's bogus?! The rambam in perek 5 clearly makes a distinction between vocal and intrumental music(although in his shaalos uteshuvos he does not). The mechaber, the rama , and the tur also do. R' moshe happens to pasken like the rambam in perek 5(although he says a baal nefesh should be machmir like the rambam in his shaalos uteshuvos).To disagree, fine. But to say the mchaber,rama, and r' moshe are bogus would be pushing it a little bit too far. Could you please explain?! Thank you very much.