Audio Systems: driving an active subwoofer, line level input, active subwoofer

Question
I have an active subwoofer but an older amp with no line/low-level out.  My DVD/CD player has a digital coaxial out that takes an RCA jack.  Can I use that output to send the CD signal to the line level input of the sub?

Thanks in advance.

Answer
What?  You lost me on that one.

No, you cannot feed a digital signal to an analog amplifier. If that is what you are asking.

Why not take the analog output to the subamp input?  That is the obvious thing to do isn't it?  You can put a splitter on it so you can feed the audio output to other amps as well.

But, let me know more if necessary.