I will ask a dumb question on power conditioners

Garebear, as you can see, your question's not so dumb.

There may be differences among some manufacturers using these terms

Bill_k says it best; power conditioner seems to be a blanket term which includes active and passive units. The active unit is a regenerator cleaning the AC line voltage by converting it to a DC sinewave and then outputting clean AC to the components. Passive uses capacitors and other proprietary electronics to remove dirty line noise and lower the noise floor.

In the Classifieds, the "AC Conditioners" listed are active and passive units, but are largely active units(regenerators).

Garebear, as you can see, your question's not so dumb.

There may be differences among some manufacturers using these terms

Bill_k says it best; power conditioner seems to be a blanket term which includes active and passive units. The active unit is a regenerator cleaning the AC line voltage by converting it to a DC sinewave and then outputting clean AC to the components. Passive uses capacitors and other proprietary electronics to remove dirty line noise and lower the noise floor.

In the Classifieds, the "AC Conditioners" listed are active and passive units, but are largely active units(regenerators).

Power distribution units have multiple outlets usually with some filtering incorporated.
That's my understanding of the different devices.

that's true. And then outputs clean AC. My bad.

The Blue Circle PLC (powerline conditioner) Thingee FX2 does a remarkable job of lowering the noise floor for a very reasonable price. And I see they've added a higher level unit on the website. (they're funny looking, but they work).

Their retailer is at
http://www.tlp-audio.com/powerConditioners.php

http://www.bluecircle.com/page151.html

Another way to go is to check out a used Furman Elite Series power conditioner. This is an active conditioner with surge protection. There are separately filtered outlets for analogue and digital sources; an important feature.
I've seen them sell for about $700-800 in the classifieds.

Start a new thread since now you are asking for advise on power conditioner/regenerators. If you have a high quality system, this is what you should be looking for.

No, Garebear. Just reading the excellent reviews. I think a new thread that is specifically asking about power conditioner/regenerators will get you replies. List your system and budget.
Also there are many for sale used in the classifieds.