@flowcharts Good stuff! About the umbilical, I’m curious if there is any difference between the 14ga and 9ga other than size. The 9ga will offer more conductor versus dielectric. But wow, 9 gauge is really big when you have it in hand. Are you using stranded or solid? I’ve heard mythical results claimed for Mundorf’s expensive silver/gold wire used for DC umbilicals, and that’s my plan for an upcoming LPS cable to my USB reclocker. Intrigued by your observations though, and curious to hear more.
Your power cable looks awesome. My research has shown that proper shunting of conducted (from the ground pin of IEC on components) RF to earth ground is > the effect of diverting to ground boxes. For example I have a customer who returned an expensive grounding box after a Whisper cable rendered it ineffective. The reason was that every bit of the multiple elements of the ground leg on the Whisper is optimized for RF transmission, including and especially the terminations. I have another customer who used SR cables with drain wires going to a ground post on their conditioner, and the Whisper proved quite superior. This is because the live and neutral geometries, metal, and dielectrics of the Whisper are better, and the RF paths are very low impedance and not hindered by external connectors whose impedance may be prohibitive or could modulate some RF frequencies in the worst case. The best channel for RF ended up being the ground of the Whisper. Instead of elongating or complicating the path for RF, it made things simple for the myriad uber high frequencies present.
I am not knocking the drain approach, to be clear. I’ve just found that the ideal ground path of the cable does 80-90% of the lifting, and the drain or drains, while effective, are fairly narrow in their RF effectiveness. This is because a drain being an antenna is receptive to specific frequencies, while a ground path of a power cable receives everything produced by a component or picked up by its chassis, so it’s much wider in bandwidth. Of course as audiophiles we treasure every percentage point, so that’s why I think you should rethink the cable in addition to the work you’re doing with the drain and outer jacket.
In a typical bulk power cable, the traditional double shield of aluminum and tinned copper sleeving will block a lot of RF, but is it a good pathway for RF? Is it a good RF antenna? It certainly needs to be to deal with what’s coming from the component, which is far, far more than what might be conducted by the cable in the room. That kind of shield is heavily influenced by the dielectric next to it, and on a durable bulk power cable that’s likely to be PVC or something with a high dielectric constant. The leg of the power cable that is most likely to carry HF energy that would be absorbed into a dielectric is closest to the worst dielectric on the cable. Not good. In this case, having a drain to a box or to a post on a strip will help, no question. But it’s like putting lipstick on a pig a little bit. It’s a better approach to remake the ground for both its primary duty of safety current conduction, and secondary job of RF transmission. And, in my opinion, to continue to focus on every single element of every leg in the same way, thinking about what each needs. Then the drain schemes and external boxes will produce those last few percentage points, if they’re also done right.
Cheers! Just as anywhere in audio, with power cable design, “everything matters” if you’re going for ultimate performance. I’m a big fan of those connectors, as you can imagine. 
Or maybe you make that a bare wire underneath the sleeving and reduce the need for “forming” against a dielectric. Just some ideas.
