Recommendation for an audiophile speaker cord that is not "bright"?

Morrow Cable, not bright but very accurate and not very pricey. They are made of woven Litz wire OFC copper. The improvement I heard over silver plated OFC copper was like night and day! They run 50% off specials for Agon members and trade ins. You may be able to talk Scott into extending that to you. They will make and burn in your cables in about two-four weeks. Nothing is stocked, everything is custom terminated to your specs from a wide variety of termination selections.


https://www.morrowaudio.com/

Kubala-Sosna. Fascination, Expression, or Emotion line.

Not helpful perhaps but Wilsons can sound bright if your ears are sensitive to those frequencies (mine are and I can’t tolerate Wilsons). I do not think speaker cable can overcome this. 

Triode Audio labs they are consistant at many shows .I personally have owned top name cables at several times there cost 
and here are as good and better in most cases .
and I own there American series digital and high power cords $5-700 they are a true bargain using only top Copper connectors not cheap gold over brass like most. To enhance and protect your 
connectors stabilant -22 is great including vacuum tube pins 
first clean all connectors with pure isopropyl alcohol .
for AC connectors Furutech nano fluid,it  is excellent but takes 2-3 weeks to dry but for sure enhances detail . Just a tip .

Elsdon Wonfor audio LS25.  These are a proprietary alloy  they are utterly transparent with no phase distortions. If you have a well balanced high end system that you like,  these will give you what you have in spades. Pinpoint stereo imaging , WIDE soundstage true speaker response.

The designer was responsible for tellerium Q cable designs but parted company and took forward some of their design principles.