It's not a matter of opinion or what I believe. Unless the song specifically says, "To receive forgiveness of your sins and gain the blessing of eternal life you must believe that Jesus died for your sins and God raised Him from the dead", then the Gospel hasn't been preached. Nothing more, nothing less. There is no other option.
As far as ministering through music, that was the point of the 6 hebrew words that are translated "praise". I reiterate, Psalm 150 clearly states what the musicians should do when we gather to worship.
Try this experiment. Part 1 How would you preach Gospel if all you were not allowed to speak and could only play your instrument? Part 2: How would you preach the Gospel if you could not play any instruments?