Mark: Dedicated lines with a clean connection for the mains at the ground rod is the first place to start. If the mains aren't properly grounded at the service entrance, you are FAR more likely to experience noise from other devices within your own house entering your system. As such, a good clean connection that is protected from the weather and potential corrosion at the AC mains / ground rod is the place to start.
After that, i would look into AC isolation using high grade, high current "old school" iron core transformers. If you use conservatively rated isolation transformers that are good for at least 40% more than what your total current draw is under the heaviest demands, you'll probably be good. I am a fan of "over-kill", so using an even bigger transformer is better for multiple reasons ( lower source impedance, less chance for saturation, reduced hysterisis distortion, etc... ). That is, so long as the isolation / noise suppression characteristics of the transformer aren't reduced to obtain higher current capacity.
As a side note, toroidal designs are WAY less efficient at isolating line noise, so don't believe the hype from the manufacturers that are using such an approach. This isn't to say that they can't work pretty well, as they can, but they will never work as well as an optimally designed "heavy metal" transformer. We are talking about differences of appr -85 dB's of noise suppression using a toroidal design compared to appr -125 to -145 dB's for an ultra-isolation iron core.
As far as balanced AC power goes, this may work wonderfully for some gear, but other gear will actually perform worse. Any gear that has been designed with polarity specific filtering in the power supply will suffer a degradation in performance. While i don't know of a lot of gear that makes use of such a design*, i do know of a few pieces. As such, you might want to check with the manufacturer(s) of your components before investing in ANY type of AC filtration devices. Just be prepared to wade through a half dozen different opinions : )
As far as power cords go, and i'm basing this on information available through the various websites from each of these companies, the Shunyata stuff appears to be more advanced than any of the others that you're using. While i know that no product works universally, you might want to think about this aspect of your system a bit too.
Stehno: No offense, as i too read and subscribe to BFS, but i have a hard time believing quite a bit of what Marty has been feeding us lately. After seeing the rack that he's using in his "Big Rig" and having used an identical product, there's NO way that his system is as revealing as it could be. At least not in my experience or opinion. That rack is a "destroyer of sonic subtleties" in my experience. Then again, i know others that have tried out quite a few different racks and also enjoy that same model, so take my comments for what they are worth. Regardless of personal preferences, i take everything that he says with a grain of salt after learning about this and a few other things. Like any other review / reviewer or person sharing information ( me included ), proceed with caution and use your own judgment. Sean
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* As i've mentioned before, most gear lacks proper filtering and power supply design. It is for this reason that something as simple yet highly effective as polarity specific filtering isn't found in most gear. Most designers / products haven't even taken care of the basics let alone advanced to something as advanced as this. If they did, the changes from one type of power cord to another wouldn't be as audible as they are.
