This post from John Piper argues that the defining sound of worship is congregational singing. I would agree, perhaps with a twist of congregational participation mostly expressed through singing.
They link to this article where the writer says
1. If we the congregation can’t hear ourselves its not worship.
2. If we can’t sing along its not worship
3. If you, the praise band are the center of attention, its not worship.
Yes! Well said! There are many more corollaries that could flow from John Pipers definition.
4. Sing songs together. Don’t just give us a few.
5. Teach us how to sing at home so that we don’t take up time learning in the service.
6. Judiciously, introduce new songs.
7l Make sure our congregations repertoire is rich.
8. Remind us that singing is a command and a fruit of being filled with the spirit.