I wouldn't call my Auteur
particularly bright, although I certainly wouldn't call them warm either. Pretty neutral to my ears. Like
@55Powers said below, I also have Blackwood. Do you have the Teak?
I've never listened to the 1990, but I did have theT1g2s though. I found
them to be painfully bright/piercing.
I actually have been using a couple of SPC cables with my Auteur to pick up the treble/detail a bit. Silver Dragon balanced 4-pin XLR with my desktop system, and Lavricables 2.5mm TRRS with my DAPs. And I also prefer my Auteur from my Opus #2 (Sabre DAC) over my Plenue 2 (AKM 4497 DAC), although this is a small difference. The opposite is true for my Utopia, which I listen to via OCC copper, and prefer from my Plenue 2 for portable listening. Also, I'm happy to listen to the Auteur from both my Denafrips Pontus R2R DAC and from my Oppo Sonica Sabre 9038-based DAC, but I much prefer my Utopia out of the Pontus.
I do own HE-560s. I wouldn't say that my Auteur are significantly brighter than the 560s from any of my rigs.
I've not listened to either of the Woo amps you mention. Based on reviews I've read, it sounds like the WA-2 might improve matters some, depending on tubes.
Have you had them long? Burn-in? I actually allowed mine to burn-in mostly un-attended for at east 50 hours before I did any critical listening, so I can't say if what you are hearing is normal for brand-new Auteur, although I know Zach burns them in some before shipping.
I actually wonder if you have some problem with your Auteur. Damaged during shipping?
In any case, sorry that you're not enjoying your Auteur