Is a dac better than an new cd palyer?

SACD players can accept an external DAC for standard CD playback (all that I am aware of anyway), so the DAC will not become obsolete in this sense. Just be certain that this holds true of the model you select. If your changer has a coaxial/digital out and/or a Tos Link out then it can be used with many DACs. The trick is finding one that you like the sound of. I did not find some of the "new" DAC's (as of a year ago) to be an improvement over the stock DAC in a CAL player, so care is needed when selecting a unit.

First of all , nice place to post the question... :-)
You will get better response if you put it in Digital.
It would be actually helpful if you specify your budget.
Generally speaking, stay away from changers…

Unlike Dekay, I am very happy with the Classe' dac I used to upgrade my CAL CL-10 changer. So far, I believe that it gave me a major upgrade in sound while preserving the party friendly changer.

I went to a used Muse 296 with my Arcam CD player. It made a huge difference and I love it.