I own both a DAC8 and a CD7. The DAC8 has a USB input, I believe the DAC7 does not. The DAC section of the CD7 is much better than the stand alone DAC8. I use the DAC8 just for computer audio. The DAC 7 and 8 are solid state while the CD7, 8 and 9 are tube. I have not heard the CD9 in my system, I probably should borrow one and compare it to my CD7. As a stand alone player the CD7 is excellent and a bargain used. I listen to a lot of vinyl and the CD7 is very smooth and analog sounding. The CD7 and CD8 do not have digital inputs, just digital outs. The CD9 has both digital input and output which makes it more versatile.
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