Topline
Topline writing on producer beats
A topline is the vocal melody and lyric you put over a beat someone else made. Get it right and the beat becomes a song. Get it wrong and you are just talking over a loop.

1. Listen for the space, not the beat
Producers usually leave gaps where the vocal is meant to sit. Loop the section, close your eyes, and hum into the space. If you find yourself fighting a synth line or a drum fill, you are in the wrong pocket — move.
2. Match the rhythmic language of the track
If the beat is triplet-based, sing triplets. If it swings, swing. If it is dead-straight, be dead-straight. The topline shouldn't feel like it arrived from a different song.
3. Contrast the verse and chorus melodies aggressively
On a repetitive beat, the vocal has to do the arranging. If your verse melody sits between the notes A and D, push the chorus to F and higher. The beat can be static; the topline can't.
4. Record the first idea before you judge it
The first melody you mumble over a beat is usually 70 percent of the final topline. Record everything on your phone. Judge later. You will lose more good ideas to self-editing than to any producer's notes.
5. Give the artist somewhere to belt
If someone is going to sing your topline live, they need a moment to lean in. Design one line in each chorus that sits at the top of a comfortable belt range — usually somewhere between E4 and A4 for most contemporary singers. That is the line they will remember writing with you.
"The best toplines don't sit on the beat. They complete it."