Bluegrass has roots in traditional English, Scottish, and Irish ballads and dance tunes, and in traditional African American blues and jazz. Bluegrass features acoustic stringed instruments and emphasizes the off-beat. Notes are anticipated, in contrast to laid-back blues where notes are behind the beat, which creates a higher energy characteristic.
Just saw Ricky Skaggs here in Athens! https://www.youtube.com/watch?v=TfDY3EdCl2U