Triode Wire Labs or NRG Custom The Five for my 300b SET tube amp?

LavriCable flies under the radar but their products punch WAY above their price. Their cables are 5N silver but just sound like music with excellent dynamics and detail. I’ve got several of their cables and many other very established members here have bought their cables and gush about how good they sound. At your price level you can buy their absolute top PC, and I think it’ll deliver exactly what you’re looking for in spades. Hope this helps, and best of luck.

https://www.lavricables.com/cables/grand-30-core-silver-mains-eu-us-power-cable/

That Fezzari bike looks absolutely sick, but the seat makes me think it feels like getting a prostate exam.  

Got it.  The cutout in the middle seems key to especially male comfort/health.  And I forgot about biking shorts having padding, which I also own and are obviously key.  And I had no idea about the chaffing issue, but that makes total sense. 

I am curious about those Lavricables now, too. How’s the dynamic punch and soundstage on them?

They’re 5N silver and nail it on both counts. I use both their balanced interconnects and balanced headphone cables in my HeadFi rig and I ain’t letting either of them go. I’m using an iFi Zen stream into a Denafrips Iris DDC feeding an i2S signal into a Musician Pegasus R2R DAC that in turn feeds a Linear Tube Audio MZ2 amp that drives my Hifiman Arya Stealth ‘phones just for context. BTW, I also use a LavriCable USB cable that I’d also highly recommend as it features dual 5N silver cables to physically separate digital and power signals that usually comes at a much dearer price from other companies. Just another idea FWIW.

https://www.lavricables.com/cables/ultimate-silver-dual-usb-a-b-interconnect-cable/

aren’t silver cables tend to be more on the cool side though? I wouldn’t want to loose the bit of warmth I have and sweetness of the 300b if the silver is too cool.

No. That’s a farce and the beauty of LavriCables. When silver cables are designed well, they’re glorious. They strike that magical balance of natural detail, warmth, and neutrality without ever sounding thin or harsh. They’re really the best of all worlds. I don’t know how they do it, but they just sound like music and I think other owners here will back me up on this. They’re a relatively unknown gem IMHO, but my bet is they’re gonna grow and their prices will probably go up.