Can a new DAC make a 6 disc changer sound better?

I have an Integra 6 disc changer that I use when I want background music or want to listen to more than one disc at random. I have the digital out running to the DACs in my Integra reciever that I use as my preamp. Are there any external DACs out there that would make this setup sound better or is it a waste of money. I don't understand why the transport would make that much of a difference compared to the DAC. I use a Philips 963 SA when I am doing more serious listening. Would a different CD changer be a better choice than buying a DAC?
I found that a good DAC (Classe' Dac-1) plus a Monarchy DIP improved an already good (CAL CL-10) changer.
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In one system I have a Sony ES changer feed a Meridian DAC and in another I have an Adcom changer feed an Audio Research DAC.

Bought both used, $400 and $300 - well worth the money.

If you bought a used one for a fair price you could always get your money back reselling if you decided the improvement was not enough or non existent.