Responses from bkauf

New DAC or New CDP?
Just my 2 cents worth - Stick with a new or used CDP. The addition of a DAC to your existing CDP will require new cabling ($$$) and will introduce jitter. 
Powerful Integrated amp for Proac Super Tablettes
Classe CAP-151 would be my choice. Sells new for $2400. I've seen them here for $1100. 
Is it worth to buy a used Meridian 506.20 ?
Sure does. I also listen to jazz and vocal and it does an excellent job with soundstaging and tone. You will like the build of the Meridian. The drawer is solid. I can't speak to the difference with the 508, but $550 is a great price. You won't be... 
Is it worth to buy a used Meridian 506.20 ?
I have a 506.20 and absolutely love it. What don't you like about the CD-72? What do you consider a good deal?