O.K. good points all. In order to learn some of these songs by playing along with the recording at first and then with other musicians, I would like to know the key right up front so I can skip trying 8 or 10 harps till I stumble onto the right one. So if I could ask Muddy it would be what key are you going to play in and then I could decide on straight or cross harp. The recordings Iam using are. MCA Best of. MCA/Chess Best 1956 thru 1964. andCharly Blues Masterworks Vol. 39.These three pritty well cover what I would like to learn. I have no musical training whatsoever so please bear with me if I don't make myself clear in my asking or don't understand some of the replys. Once again thanks to all. Slim