Do I need upgraded power cables?

Once again the cable question.  Do cables make a difference yes.  Just did a shootout with power cables on an integrated and CD/SACD player.  One cable was $450 and the other $6,000.  We switched them back and forth.  The result was we preferred the expensive one on the CD/SACD player the less expensive one on the integrated.  Price is not an indicator of synergy with a system so you need to experiment.  If you can actually get loaner cables to test, that's the best you do.

I've had the Kimber 8ts and Silver Streak about a month and things are sounding too bright.

What cables/interconnects were you using before?  I’d wait til you have at least 150 hours of playing time on the Kimbers before making any firm conclusions, but it sounds like they could be a mismatch for your system.  Your speakers are known to lean toward the bright side so cable matching becomes even more important, and if it’s still too bright after 150 hours it’s time to move on to something else.  I have recommendations for some very good used cables you could try that’d likely make a big improvement both in brightness and imaging/soundstage for not much $$$ if you’re interested and the Kimbers don’t work out. 

• What cables/interconnects were you using before?  I’d wait til you have at least 150 hours of playing time on the Kimbers before making any firm conclusions, but it sounds like they could be a mismatch for your system. 

I had an old set of Monster Powerline 2 for speakers. Between CD player and amp was a Cardas Quadlink. (I thought the silver streak would have sounded much better than the Cardas, but it wasn't to my ears) Between Turntable and amp are the ones that came with the Pro-Ject. I would be interested in the used cables you mentioned.  Thanks

I’m pretty confident these will bring significant improvements over what you’ve had to date. 

https://www.usaudiomart.com/details/650192681-acoustic-zen-satori-speaker-cables-25m/

https://www.usaudiomart.com/details/650192584-acoustic-zen-zero-crystal-matrix-reference-ii-10m-and-15m-rca-and-balanced-11-pairs/

@bzawa take a look at this link

• What i have found makes a good cable

It talks about what elements of cable design can improve performance.

Cable are the heart of my system and improves every aspect of audio system performance.

I've applied cables to systems ranging in price from $300 to $70k and in all cases significant improvements were achieved.

The link also identifies a couple of brands that use advanced design techniques and materials

Good luck with your quest, steve