Drumbeat and Drum roll

Drumbeat noun - A rapid or overwhelming outpouring of many things at once.

Drum roll and drumbeat are semantically related. In some cases you can use "Drum roll" instead a noun "Drumbeat".

Drum roll noun - The sound of a drum (especially a snare drum) beaten rapidly and continuously.

Drumbeat and drum roll are semantically related. You can use "Drumbeat" instead a noun phrase "Drum roll".