AN Niobium versus Tantalum resistors?

In my Khozmo passive, the shunt resistors are the Takman REY metal film resistors and the single fixed series resistor in each channel is the Vishay z foil naked resistor.  As described by PW,

"their utter transparency can prove too ruthless and become overtly clinical" 

This becomes a personal choice but they are revealing for sure.

Regarding the Amtrans AMRG resistors in my Hattor BIG preamp, I believe they offer a couple of levels of resistors - mine are the black carbon film resistors.  All I can say is that they sound very nice with a good balance of detail and musicality.  The big Audio Note Silver Tantalum non-magnetic 2W resistors I used to replace the Shallco VC in my buffer also sound very good and seem to be well-balanced.

My favorite combination is using the z-foils in series positions and the AN silver tantalums in shunt positions. The higher wattage silver tants sound a bit richer but don't fit everywhere. 

I haven't tried the Niobiums. 

Takman's take on induced noise makes sense with the naked Vishay, but then, induced noise would predict lower transparency, resolution. I believe pretty universal experience TX2575 highest resolving, transparent resistor. Issue with these, wattage and lack of flavor, as previously noted these won't supply your needs.

In any case I'd like to hear your impressions of these resistors if you decide to try.

 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.