Speaker cables with good timbre

Silversmith Fideliums are excellent. And affordable.

I replaced $6K cables that are now relatively junk.

Truth of timbre?  Cables have no timbre, truthful or otherwise.  All dependent on cable synergy with source component and loudspeakers.

+1 on the Acoustic Zen Hologram. They don't add or take away anything from the soundstage. I'm also using Acoustic Zen speakers so they make all the more sense.

Cable preferences are like assholes -- everyone has one!  Throwing my hat into the ring here, I have used a full loom of Morrow "7" cables, MA-7 IC,s SP-Speaker cables.  I liked them and they were a good value for the money.  However, I then went to Shunyata Alpha v1 speaker cables and then Shunyata Sigma v.1 speaker cables, and they are just fantastic in my system.  I have a full loom of Shunyata power cables, Sigma IC's and a Shunyata Everest power conditioner, so I am a fan boy.  In my system and to my ears, they are exactly what you are looking for.  Of course, cables are dependent on a lot of different factors relating to your components, so YMMV.  But for me, Shunyata is great and highly recommended, as is the Everest!

if you're going to buy the speaker cables don't buy anything OFC that's the worst wire for audio, you should look at any company that's using OCC single crystal cables that is the best wire for audio proven for over 50 years, though there's many companies that have it like harmonic technology acoustic Zen, zavifino and many others some charge a lot and others are more reasonable like harmonic technology and acoustic Zen.