What process do you use to purchase cables?

Mostly listen.
Read reviews and posts and peruse systems to see if there's any concensus for synergy with component brands. Easier to find that between brands like Plinius and Dynaudio or Leben and Devore.
Try to ascertain hook up wire used in components. In days gone by, Plinius used Siltech and it was a good bet that would match well.
In the end, listen and listen again. I used to to think it was like lightning in a bottle and only by the empirical method would you find the best match. That seemed supported when I put a Stealth Cloude 99 (or was it a Nine?) full on a modded AES PH! DJH and couldn't believe how much more fidelity I heard.
That cord cost more than the component. Cables changed context and became components.
In the. end, some designers/builders seem to hit my sweet spot and it doesn't seem like there's necessarily a mysterious synergy that has be searched out for each component - that would change with every system and set of ears anyway. Find what you like
So, it was listen listen listen. For me, in order of preference:
Interconnects: Dynamic Design AE15, Gabriel Gold Infusion v2, Gabriel Gold Rapture r
Power Cords: Dynamic Design Titania GS, BMI Oceanic Statement Classic Gold, Dynamic Design Heritage AE15, BMI Whale Elite
Speaker Cable: wellllll, I use Duelund 16gax2 (~13ga) tinned copper. 

Process???

1.   Check the cable doesn't cost more than $200.
2.   Read what Miller says about it.
3.   Listen in my system for at least 3 weeks.
4.   Ignore what Miller said.
5.   If cable sounds good, buy it.

@clearthinker 

lol

I picked a manufacturer in the northwest near my home.  Blue Jeans Cables is their name.  Their product is well constructed, low capacitance, and very affordable.  My theory is so long as the cable is well constructed you don't need to spend a tone of money on them.  I also think cables are one of the least destructive components in regard to good sound.

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