AN Niobium versus Tantalum resistors?

 these won't supply your needs

excluding compoents from consideration based on pure speculation made on the basis of what you read is rather unwise IMHO.

@pesky_wabbit I very much doubt the Z foils will deliver what OP desires in this particular case, reason I suggested Takman carbon films over Z foil.

And my suggestions not based on pure speculation as you speculate in regard to my experience. I have in fact been using the Z foils for years, many in my Merlin BAM, in previous dac, in former phono stage, in Art Audio Carissa Sig, in my present 300B monoblocks. So, plenty of experience, again, I doubt these will give OP what he desires. Also, wattage will be of concern, TX2575 just over 1/4 watt, yes, you can stack for greater wattage capability. In the end I believe OP is on correct path, he's done due diligence here.

Caddock MK132 have the signature the OP is looking for.  These are discontinued, however their replacements the MK232 should fit the bill as they share the same construction and have undergone only minor changes for Rohs compliance.

I've heard many things about the Z Foils and the Takman paper regarding their design is a logic aligned with many experiences I've had. We all have to prioritize based on the synergies and brands that resonate with us. In a perfect world, I would love to try them. Absolutely the only way to know anything for sure is to try it yourself.

If the AN resistors are too euphonic or feeling too inaccurate, I might go to the z-foils. Just when I think I master the logic of my DIY, I will get shocked with a failure and go searching in new territory :) Isn't that the truth?

Regardless..doesnt sound like too many people have tried Niobium.

doesnt sound like too many people have tried Niobium

think the price has scared a lot of people away. Would be most interested for you to post your findings