how do you know if you need a dac ?

have always been into vinyl and recently decided to get out of it and bought a Ayre CX-7 cd player.    while it sounds just fine, I read in the forums about members getting dacs.         

how do you know if you need one or not ?

what benefit would one add if any ?
If you like it, you don't need a DAC. Trust your ears.
Does your Ayre CX-7 have a digital input? In a lot of cases people get DACs to stream music online. If your happy with the CX-7 no need for a DAC  and if it has a digital input you're fairly future proof.
Why would you get out of vinyl?  I can't imagine going digital has been a sonic improvement.