Ok, Call me crazy, but I am a newbie who has become obsessed with creating a hi-fi system that will play a MP3 jukebox (of my own creation). I got the Creative Audigy 2 ZS sound card, put a big hard drive (160 GB) into my old PC, and loaded all of my music onto the PC (at higher quality--is it 312 kbps?). My sound card has both 5.1 out connectors (I use mini to dual RCAs) and a coax digital out. My coax out only produced stereo on my present receiver (Pioneer VSX-411), but the 5.1 connectors work great. I have a TV out video card that I use to put the computer screen on the TV, and I can watch those cool visualizations with music while managing windows media player like a jukebox. I use a cordless keyboard and mouse to control the computer. Amazingly, it all worked like I thought it would (that rarely happens when I have these hair-brained schemes).
Next step--my audio system is pretty poor, and I want to upgrade it. In terms of receivers, what will get the most out of this system for MP3s? Looking at product specs, I have seen a few features that make me wonder:
1) Some receivers say they have MP3 decoding. Is this a must if I want to get the most out of this system? Actually, if I am using the 5.1 inputs, does that mean that the decoding is already done by my sound card? I assume if this is the case, this feature is useless to me (unless the decoding on receievers would be better than that on the soundcard). My uninformed guess is that the MP3 decoding is just DAC, and as long as the DAC is in all channels, I will get surround stereo when using the coax out on my soundcard (if my guess work is right, that would mean that my present receiver only has 2 channel DAC). But if the DAC on my computer is superior (or equal) to that on the receiver, I guess I can just stick to the 5.1 input.
2) Some receivers have integrated USB ports. I am not sure how important this is if I have a good sound card. Perhaps this is also useless in my setup unless I want to get on-screen display of my MP3s like the Onkyo NR 801 has.
If these features do not really affect me, then I suppose I will just seek a good receiver. If they do affect me, I will consider the particular models with the MP3 friendly features. Any opinions?