A voice of dissent. A vote for the $10K CD player.
A high end RedBook player is still worth the money. The digital sections of CD players have improved quite a bit over the last five years. Today, digital horsepower is fairly cheap. The mid priced players ($1K-$3K) have come a LONG way.
The improvement in mid-priced players has significantly raised the bar for all products in all price ranges. The devil is still in the details, and the finer points of design and implementation. To achieve that last bit of awesome sound requires more than just a good and well implemented digital filter. The product engineering, chassis, transport, power supplies, parts selection and analog sections must all be top notch. One DAC in particular (quite expensive) has paid specific attention to these (mostly analog) details. Despite the fact that this DAC is 5 or 6 years old, it is still better than the latest dCS stack, or any current standalone player (including my new and "current" big budget Wadia 861se). But this DAC also costs several multiples of the 861se retail price.
As an example, look at the DAC offerings from Audio Note. Very simple digital sections. Very well designed and highly thought out analog sections.
I agree with most of the posts, you can keep buying a $3K CD player every two years, and continually improve your "sound". But none of those players really can touch the $10K players of today. So why not get out of the upgrade game, same your money, buy a single CD player, and enjoy better sound from the get go.
I think this is especially true today while we wait for the music industry to get over their hangups with physical media and finally say goodbye to optical disks. Just make sure that fancy player has a digital input capable of handling 24/96.
