power conditioner

..tried many, they all have warts I cannot live with.   You must try them inl your own system to hear if the colorations et al are acceptable to you.

@falconquest to your point "And it's not like they wear out so your investment can last for many many years" this is true, however, in the case of an actual surge I come to learn (by talking to electronic repair shops, not first hand experience) that the overwhelming majority of conditioner use some kind of MOSFET and those components can only withstand one (1) surge and then they are of no value (i.e. they have sacrificed themselves to save the rest of the gear). Further, and from what I've read and been told, trouble is "small" surges that you may not notice could also do irreparable harm to the MOSFET without the end user even realizing the protection is gone.

One electronics guy told me if one gets a direct lightning strike there is no in-home surge protection device that could withstand that. The voltage could simply arc across whatever stands in its path and literally fry anything "in its way".

Still, I agree its better to use surge protection than not have it at all.

I can only speak for myself, based upon my two audio systems I have to say yes, I definalely hear improvement by using dedicated AC lines, and further improvement with a good high quality AC outlet. In addition to that, I also hear an improvement when using some type of power conditioning. Many times my amp sounds better when plugged directly into the wall.
Audio equipment reacts differently to various power conditioning, so it's a matter of trial and error and/or reading various reviews and hoping what you read about works in your situation.
Just yesterday I received my Power Core Technologies 1800, in my system, it's a killer out of the box and very reasonably priced. 
I agree with Lowrider57; "The goal is to lower the noise floor, provide stable power, and not restrict the sonics of your system".

"..they all have warts I cannot live with."

Hi stringreen,

The Ayre L-5xe is not one of the AC Enhancers I was referring to.

Best to you stringreen,
Dave

How important is power conditioner for musical system

The system can work without power conditioner so one is not critical to the system.