Will an outside DAC over ride the tubes

Yes, the digital output of your player bypasses the player's internal DAC and tubed output stage.

Ghostrider45 is quite right, an external DAC would function in place of the player's internal one. This means the 12AU7 tube in the analog output of your Cayin would be bypassed. However the tube itself will continue to operate, and eventually wear out, unless it is removed.

Both Ghostrider45 and Tobias are correct.

I have never seen the purpose of a digital out on a tubed CD player. Digital inputs would be much more helpful.

By the way, if you do this don't remove the output tube, but replace it with a cheap one. Your output stage may require on even if the output stage is not used.

hi restock:

i have a vincent cd s6. i can remove the output tubes when the cd player is used as a transport.

Do you dislike the sound you are getting with the unit? You could get a tube DAC.