I am planning on buying an iMac in the near future, after the update. This will make me a switcher. I have found substitues for everything hardware- and software-wise (other than CAD progs), everything that is, except multichannel audio. I have a good Boston Acoustics 4.1 audio setup now using a Creative SoundBlaster Audigy 2 Platinum. I might upgrade to 5.1 or 6.1 in a year or so. I know the iMac supports multichannel audio via optical out, but my speakers are not directly compatible as they use analog plugs. Also, is the signal to noise ratio lower than my audigy (~115 dB)? I have viewed a previous thread on this topic here, but it only suggests an external Creative Extigy card, which I have already thought of. Basically, I want something reasonably inexpensive (like the Audigy was at $200) that has a good amount of inputs and outputs, a high s/n ratio (above 100 dB), and most importantly, compatible with OS X (as in, it has a USB or firewire connection that the mac will use for the audio out with matching software). I really want to have a stand-alone system without having to siphon out the optical from my mac into my audigy, then out to my speakers (which I couldn't do if my windows desktop was off). I have also looked at M-audio's products, but they don't seem to have what I seek, or it is way too "professional" for my uses. Has anyone succesfully hooked up a good multichannel system to the iMac like this?