im going to put this in as many forums as i can....

I did notice a slight bit of grain or edginess in the high treble(flutes & such) when I first got my new amp & speakers.Before I spent big $ upgrading from the PST-8 I decided to swap out the $0.50 wall receptacle.Went with the Voodoo Audio receptacle along with landing the neutral wire for the receptacle directly to the main lug instead of the common neutral bar,pulled the ground from the common ground bar,terminated with a 1/4" eye connector & landed under the main ground lug with star washers on both sides of the connector & replaced the breaker with a new one..The noise floor is so clean now you could hear a pin drop in a concert hall..
Disclaimer:I am a Master Level Commercial electrician & more than qualified to perform the tasks I describe.If you are NOT a Certified Electrician do not attempt any such modifications on your own!

Furman makes great products. 

freediver  I too am a believer now.....

+1..I have used the PST-8 for many years in main & backup systems.Compared them to several much more expensive conditioners & never found the need to upgrade.