ww korkor,
after looking into the subject for the past 6 mths or so, i found that a power conditioner can mean many things and there are many different designs that does different things. common power conditioners like avr (automatic voltage regular) used for PC and home AV applications, or those that comes with built in line/power protection or surge protector also offer some kind of conditioning and filtering. most people buy it to protect their equipment against over/under-voltage, surges and such. some even buy one because they need a power bar to use one outlet on the wall to split for several appliances. many of the units comes with filtering to remove emi and rfi from the powerline but most "cheap" ones are purely marketing. they may shield away some noise but also hinder power (like a coil that many installers use in the past to remove aeroplane noise).
what i am really seriously looking into is a power conditioner for audio purpose. not a surge protector (a fuse can handle that), not a voltage regulator (an accuvolt or similar product can handle that) and not a power splitter/volt meter (a distribution block with voltmeter can handle that). one that when plugged in and out, audible differences in the sound quality can be noticed immediately. a power conditioner that removes noise from power supply so that the sound system background is pitch black quiet and music flows out effortlessly, naturally without hinderance. highs, mids, lows, air and space becomes more prominent because the background noise is reduced or eliminated. this goes one step above cleaning.
i guess this is a bit far fetched for car audio because most car audio systems are not revealing enough to really appreciate such devices. a majority of enthusiast is even stuck with low-loss industrial grade "characterless and boring" cabling like B and C or even cat-5, have no regard for proper powercords/powercable, stuck with 50cent components in crossovers and expect installation to be free with purchase. definitely, they will not be ready to accommodate such devices in their system.
