Hi. So i have finally put together my first system, and am looking for advice on a digital/analog converter so that i can play the majority of my music collection through my new set-up. I am using a rotel rb-1080 power amp, and a rc-1082 preamp to power my infinity intermezzos. From what i understand my airport express had a sp/dif output, and all I need at this point for quality audio is the digital/analog converter to bring the music to the preamp. Any suggestions? From what I have seen these seem to be quite expensive and was looking for an affordable alternative. Thanks!