Interconnects/Cables of your choice, and why?

I started buying "specialty" audio gear in the mid to late eighties. It was immediately obvious that different cable sounded different.
For twelve of the subsequent years, I was in retail. During that time, I had the opportunity to experience a number of different brands with a wide variety of equipment. 
None of what I say invalidates your opinion. I don’t have your gear/ears/room/taste etc. But I have considerable experience over time.
I subscribe to the "loom" approach to cabling: source your cables from the same manufacturer so as not to compound the inevitable imperfections. 
Til recently, I was a "tube guy," and my cable of choice was Nordost. Open, fast, and clean with minimal editorializing. I had pieces from Heimdall2 to Valhalla2. (I didn’t even want to hear Odin.)
When I switched to Hypex class D amplification, I experienced a lack of synergy with the Nordost.
Long story short, my loom is now Furutech. Perhaps not as "airy" as Nordost, but neither would I say it lacks air. Rich, "musical," timbrally accurate, quiet background,  etc. 
Pro tip: if you can get the manufactured-in-Japan product at a reasonable price, probably used, I highly recommend them. On the other hand, their DPS-4.1, DAS-4.1, and DSS-4.1 products can be had in DIY form for a large percentage of the performance at a small fraction of the price of the MIJ line. You can also buy them pre-made from authorized resellers. Have fun!

P.S. It's telling how many boutique cable companies use Furutech terminations.

"specialty" audio gear 

This is where differences in quality cables and interconnects becomes most obvious. High gain stages, careful design/topology, top notch parts, made for an intended purpose which it fulfills, etc. solid-state that can sound realistic rather than mechanical. And with tube amplifiers that are top-notch such as those made by Western Electric and Audio Research, and Conrad Johnson. 

When I switched to Hypex class D amplification, I experienced a lack of synergy with the Nordost.

This makes sense; considering how they arrived as such high measurements. I stick to either class A or class A/B, with careful considerations.

Long story short, my loom is now Furutech. Perhaps not as "airy" as Nordost, but neither would I say it lacks air. Rich, "musical," timbrally accurate, quiet background,  etc. 

Thanks for sharing this. Sometimes total transparency is not what we’re after because it can be tiring to listen to. 

Most of the time during the last 30-odd years I've used interconnects bought from Best Buy, back when they sold stuff by Monster Cable. Never thought much about the finer details, so they sounded all right by me. I still have a few pair that I use for short-distance connectivity.

When I began to upgrade some stuff in my system after a lightning strike, including new components, I looked around on the Internet and saw that Blue Jeans cables were viewed favorably in the group of low-cost/better quality interconnects, so I replaced some of the interconnects with those. I also use Blue Jeans cables for my coax connections between my CD transport, my Wyred4Sound Remedy Reclocker, and my DAC.

For the longest time of anything in my system I used 12 gauge copper speaker wire from places like Best Buy, Home Depot and Lowes. After looking at some photos from Morris Audio about their speaker cables, I started experimenting a little on my own with smaller gauge copper wire.

Right now I'm using stuff I bought from Amazon to create my own speaker cables: (1) 24 gauge 99.98% pure copper wire (or so they say); (2) copper foil tape; (3) 1/4" OD / 3/16" ID clear vinyl tubing; and (4) better quality banana plugs. I think this has made a drastic improvement in the overall sound of things.

• https://www.amazon.com/dp/B0F5Q8WBFD?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1
• https://www.amazon.com/dp/B0CRP8FXKC?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1
• https://www.amazon.com/dp/B08TZXH39Q?ref=ppx_yo2ov_dt_b_fed_asin_title&th=
• https://www.amazon.com/dp/B0D6NJ8JKC?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1

Does it sound like the stuff most everybody listens to on this forum? Probably not, but I'm happy with the results. CDs, LPs and FM radio sound more spacious, lifelike and natural to my ears, and there doesn't appear to be any interference coming out of my 1994 Vandersteen 2ce's during playback.

If I upgrade anything else anytime soon, it'll be a better tube preamplifier. Seriously considering the Icon Audio LA4 MKIII that's advertised on this site.

Speaker: Audience AU24SX

Exceptionally thin, light, easy to manage, yet sound superb. I've tried others, and have always returned to Audience, with a few upgrades over the years.

XLR interconnect: Audience AU24SE

Haven't tried many others, but feel no need to do so.

Power: 2x Ansuz A; Ansuz Mainz P2; Hijiri Nagomi H-DC1115; Shunyata Black Mamba

All excellent, in my system, and connect to the also excellent Mainz 8 X-TC "high-end audio power distributor".

AES/EBU: Kimber Kable KS2120

The only cable that I've used between my Dacs and CD player.

USB 2.0: Supra Excalibur 

relatively inexpensive, but the music, including DSD files, sounds terrific coming from my Mac Mini M2..