The History set is this one. It's available for the price of 3 Naxos' CDs: http://www.jpc.de/jpcng/classic/detail/-/hnum/4094973/rk/classic/rsk/hitlist A direct online RealPlayer file comparison shows great differences in the remastering of the recording. http://www.jpc.de/jpcng/classic/detail/-/hnum/5879113/rk/classic/rsk/hitlist History's set has almost no background noise while Naxos' CDs have a noticable tape hiss and fuller piano sound. I wonder which recording is preferable. Best wishes, Peter Ramson