Power Conditioners to reduce Sibilance

While I cannot argue with any of the suggestions above, I believe there is no "universal" right answer as to what is causing the sibilence in YOUR system.

I have been chasing a sibilence problem in my system, taking the suggestion that room treatment should be the primary target. I chased my tail with treating first reflections, rear wall reflections, covering all windows, etc.

Then it dawned on me to conduct a simple troubleshooting test.....I used headphones hooked to the tape out of my ARC SP8 preamp. I figured that would take the room acoustics out of the equation. Put on a troublesome LP, and the sibilence was still there. So my problem in my system is somewhere between the turntable, cartridge, I/Cs, and preamp. It is not the room.

So, I'm now changing out I/Cs between the TT and preamp to see if I can solve this.

The moral of the story....I dunno....keep trying! ;-)

I doubt cables will make a difference.

Adam, I know there isn't much faith in cables changing the sound of your system, but I decided to mention this to you anyway....
Is your speaker cable a bi-wired pair?
If not you must be using the B&W jumpers? My speakers sounded terrible with a single run of speaker cable using B&W jumpers. Midrange and trebble were out of control. I changed to same cable but a bi-wired pair and I could not beleive the improvement. At least with my speakers, I noticed a huge difference. If you have someone to lend you a pair of bi-wire cables, try 'em out. See if that will change anything. It was a big and positive change with my N803s.

The bi-wire suggestion has come up in comments regarding my system and is now something I am considering. I use XLO ultra 6 and the bi-wire version (XLO ultra 12) sells for $50/foot in Canada. I may have to look into it but that is a little steep for my student budget.

You could actually find another used single run pair of the cables you already have and just double your run. Find a place that will let you audition a pair so you don't waste your $ on something that will not produce desired results.