What exactly does a DAC do?


I have a NAD cd/dvd player that I really kinda like, but I would like better audio for stereo listening, but I have I some very fundamental questions for any patient souls out there.

1. What does a DAC do?

2. What is a transport? Is there such thing as a pure transport?

3. Would a DAC be beneficial in my rig?

4. Would a standard DAC work w/SACD, if I upgraded later.

Any input is appreciated. Google is not smiling upon me.
dubzilla
I would not recommend older DAC's. DAC technology has come a long way in the last 2 years, particularly with upsamplers. Used ones are available and can be modded.
Are there any *affordable* (under 1k) DAC's you'd suggest, Audioengr?

Those Muses look really good, btw, Swampwalker.

Thanks for the heads up everybody.
I strongly disagree with jfrech, agree with audioengr and disagree with swampwalker.

Look around?? the new Inexpensive DAC revolution is upon us and they all sound good to great.

Modded P.T.3A
Modded Art DI/0 130.00 to 650.00

aDac 350.00 to 525.00
Scott Nixon tube dac 250.00 to 550.00
Channel Island appr. 450.00 inc PS

and a couple more, going used? Bel Canto DAC1 or 2

Prices range from 250.00 up to and probably above your budget for the PT modded.

Modest CDPs have modest crummy DACs, simple........