Simplify the following text for a Grade 8 native English-speaking person.
Original: Generally , it had seven strings , five of them tuned like a violin with a low d added to the bottom ( that is , dâ `` gâ `` d' â `` a ' â `` e ) with two strings off the fingerboard which served as drones and were usually tuned in octaves .
Simplified: It usually had seven strings , five of them tuned like a violin with a low D added to the bottom , and two other strings for drones .