My suspicion is that the Marantz is simply a more enjoyable CD player than the Densen ever was. I owned a Densen B-410 for a while which was purchased off the back of very good reviews and a pretty short demonstration where I praised how 'non-digital' it sounded. While that were true, longer listening sessions established a pattern very quickly in that I never listened any further than around 1/3 of the way through a CD album. That's when it became apparent that the Densen just sounded boring and had no sense of timing or rhythm, so I was hitting eject after about track 4.
I sold the Densen and the next CD player I bought cost me £5 from a car boot sale and was a Marantz CD53 and upon listening to it, I found exactly the same as you're finding now. A very musically capable and engaging player. It lacked the refinement and tonality of the Densen, but I was listening to CDs all the way through again.