Decided to change my cd player, suggestions please?


Ok so I guess this is as much a change just for the sake of change, lol, as tbh I am pretty happy with my setup but it has been the same equipment for the last 3 years so just what the heck, lets fiddle.....

So present equipment is:
Krell KAV250A
Acoustic Research LS2
Krell s-350
Usher cp-6381

Now i listen nearly exclusively to rock, mostly modern rock like Avenged sevenfold, stained, shinedown, saving abel, halestorm etc etc. Some more classic rock if I am feeling mellow.
I do not believe anything much else will ever grace my systems

I fully realize I may take a step backward or two but if there are far more expensive players out there there may be one that suits my ears better.

Budget is up to $4k used or new

Any good suggestions please.
128x128uberwaltz
Gamut CD3 bested my PS audio DS. A lot to say. If you find one buy it. 
Regards 
All the ones mentioned here are good CDP but not in the league of gamut CD3. That CD player made me a believer on shinny disc for real.
Esoteric and Ayre are on my watch list
However somebody early on did suggest possibility of keeping the Krell and running it through a dac.
Anybody have experience with this type of upgrade, just using my player as a transport and if so what dac may give a benefit?
it's common for people to use a separate transport if they think a different or newer DAC will give them better sound

Nagra makes a DAC for $30,000 - see if it sounds better to you
Not quite what I was asking I think.
More on the lines of would running my Krell through a dac make any appreciable difference to the Krells existing "sound" or just better to go for a differing player altogether?