What process do you use to purchase cables?

The opponent of cable differences has to maintain that *all* testimony regarding differences heard can be traced to unconscious or conscious bias. That is hardly proved and may not even be *provable.* But...thank you for setting the bar so high for your position. If you manage to leap over it, with more than mere assertion or scraps of evidence, it will be a monumental discovery for both audio and psychology! In the meantime, since you like my article posts, here's another.

The biggest issue for me in regards to reviews, I'm trusting them less and less. Mainly because they are either paid for or sponsored. Every review seems to be glowing. Not everything can be the best 

Quote from the article linked above:

With these measures the present work was able to prove through direct psychoacoustic testing that two different analog-interconnect pathways can be audibly distinguished.

In plain English yes we can hear differences between wires.  Thank you hilde45.   

For the record I was around back when they were doing the Pepsi challenge all over the place. They were so eager to give away tasty soda pop I was only too happy to swill it down! Every single time they would ask which one do I prefer? And I would say, "This one's Pepsi, that one's Coke." But which do you like? Which they like to phrase it that way because most people prefer sweet, and Pepsi is sweeter than Coke. But all they proved to me was how easy it is to tell the difference. 

So easy to tell, yet an awful lot of people pay so little attention they had no clue. Same here.

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.