"Acceptable" worship music is a surprisingly controversial topic within the Church. Everyone has their own taste, and many Christians attempt to impose their personal tastes on the Church at large. Today's image was inspired by a recent debate I saw between a defender of contemporary Christian music and a man who believed only pianos and organs should be used to praise God. He used a variety of crazy reasons to oppose other instruments, such as how drums were used to drown out the screams of children being sacrificed to Molech, and how the Jewish temple was mostly an outside environment.
But when the Bible speaks of music, it doesn't seem to put any restrictions on any instruments. It mentions several of them by name, such as the timbrel, and several others by type, such as stringed instruments. Ironically, it doesn't mention the piano at all, which isn't surprising, since pianos didn't exist at all before 1655...
When it comes to music, there will never be a right or wrong answer. What matters is that God is the centre of worship. That can be done with drums or pianos. It can be done with organs or guitars. Whatever instruments are played, the important thing is who it's being played for. If for God, there's no sin in it.