Okay Amir (if that's ASR's Amir), I also happen to be a beta tester of audio cables for a boutique manufacturer (GroverHuffman.com) for over two decades. No, it is a subjective test after burning in cables and hearing other manufacturers high end/expensive cables (some, not all obviously). No, we do not use controlled listening rooms or test equipment. So, his business model is based on his electrical engineering experience of almost 60 years. He is also successful with world wide distribution. His problem is that he charges too little to satisfy many high end audio equipment owners as his cables lack the prestige of ownership (versus Nordost, Transparent, Siltech, Synergistic Research, Shunyata, etc). I find fault with many "high end" equipment owners who base purchases on price rather than value (musical). He has loaned cables for use at audio shows in high end systems where they just trounced the other known high end cables (High Fidelity cables being the absolute worst-luckily now defunct). I've heard many cables which sound great in high end systems as well, with very high price tags (such as Masterbuilt cables used to demonstrate Von Schweikert speakers). I've even chosen a Synergistic Research high end digital cable over his ($200-great value) but at substantially higher price after auditioning half a dozen.
So, I don't have the hubris of being a golden eared reviewer of equipment or tweaks but I do have ample experience in listening/experiencing sound (and music) to be considered a critical listener. I have friends who are superior to me in their critical listening capabilities who are well known (one a producer, another a producer/remastering engineer and lastly my electrical engineer friend who built every type of cable as a business and many types of tube equipment that measures closer to solid state than old tube sounding gear (he also owns a patent he wrote/submitted himself) on cable manufacturing.
In other words, I trust what I hear more than I trust measurements. Measurements are helpful, hearing is believing (and everyone hears differently).