If you sit down and listen to the first 3 DP albums, you will hear some amazing classical mixed with heavy rock. At that point, Blackmore was still coming into his own, but Jon Lord was already there, having first been a classical musician before moving into heavy rock. I remember being blown away with some of the things Jon Lord was doing with a Hammond B3 first time seeing them live in '70. Truly an incredible musician. R.I.P. Mr. Lord.