Complex sentence: Many milongueros will not dance to a song sung by a female vocalist or (out of great respect) Carlos Gardel--some take this preference further and will not dance to any song containing lyrics.
Split into simpler sentences: Many milongueros will not dance to a song sung by a female vocalist or--out of great respect--a song sung by Carlos Gardel. Some take this preference further and will not dance to any song containing lyrics.