All power conditioners steal power.
@clearthinker
This isn't entirely correct. A good power conditioner will do nothing of the sort.
Many 'conditioners' are passive devices and so probably do limit current (and so have a voltage drop) but if the conditioner is an actual bona fide conditioner, it will not only clean up the power but it will also insure that the output voltage does not sag and current (up the limit of the conditioner) will not be limited.
There are very few examples of actual power conditioners in high end audio. PS Audio probably makes one of the better ones out there.
There is a company called Elgar that made real power conditioners a long time ago (they got out of that market in the early 1980s). Their conditioners had guaranteed distortion specs and regulated the AC line voltage. They made some that could handle 28 Amps! This means your entire room could have clean power. If you run across an Elgar it will likely need refurbishment- new filter capacitors in its power supplies and so on. They are built for 24/7 service and use a sophisticated system to insure that the AC they produce is clean with no voltage drop.