There are more factors at play than signal-to-noise ratio. There's also compression rate and impedence. There seem to be other factors, as well...but I'm getting out of my depth now.
The creative nomad has okay response when hooked up to a stereo, but it's not cd quality, even cranked to the max settings. I've a PD Hercules stand-alone mp3 model that does a much better job of sound reproduction as a home stereo. Good enough for my damaged eardrums. I suspect the ipod would leave me wanting..? But I'm not above trying new things. It's just I'm completely satisfied with the current setup. BTW, I use the nomad pukebox in the car now. My car has lousy cardboard-type factory speakers, so I don't care about sound quality too much there.