Well those are two routes I've been looking at myself... Belkin PF60 or building a few of the Felix filters. I was thinking of just going cheap a simple with a couple of the Tripplite Isobars, but something about those things doesn't sit well with me. Perhaps they are just not audiophile approved enough for me Oh, and yes, the PS Audio Powerplants do voltage regulation, it's one of their key features.
The PF60 has six separate filters, one for each of the six duplex outlets, and one is a high-current filter so it would meet all my needs. Also has trigger/delay capabilities which is a plus and you can get them for $200 through Belkin. Seems like a lot of features packed in for that price, which makes me wonder where are they skimping.
The unit i got is the PF40 which is the four channel version, if you look at the internal pic i posted, the far right channel is the "digital" section with two chokes, the two channels in the middle are identical (audio&video) except for the left one is switched, and the far left channel is also switched and only has two caps and a ferrite bead, thats the "high current" output.
The two switched channels can be turned on/off with the power button on the front, or you can feed it an AC or DC signal in the back to trigger them. The delay function is a set time, once triggered it waits 3-4 seconds before turning on those two channels.
The far left board has a metric crap ton of MOV's to withstand a lightning bolt from the hand of god, and the rest of the board is a mystery to me. All i can make out is the transformer runs a positive and negative 12v regular to feed a quad channel opamp, what its doing i have no idea. Apart from the simple remote trigger logic, the front panel displays voltage & current, and that's about it. Its a nicely made unit but there is nothing clever or "expensive" inside the unit, i would say the bulk of the cost is the pretty enclosure. The reason i liked it was up until now i was making separate units for different equipment, at least now i can have it all inside the one box, and with the PF40 there is plenty of room inside the case as it has two less channels than the PF60. For example there would be plenty of room to mount a Hammond 193 in there connected to a few outlets.
For the same reasons that the coil of wire that makes up the primary of a power transformer also doesn't appear as a short to an AC line supply. (The choke can be considered a power transformer with one winding, and an airgap)
That makes perfect sense now you say it. Though that does starts to blur the lines for me on the differences between a choke and auto former, apart from the take off taps aren't they essentially the same thing being a single winding? Reason i ask is i have a huge 1300watt autoformer here.