As an objective audiophile, I have occasionally been surprised by the unexpected:

I decided to test speaker cables to show that the differences are insignificant. I expected to demonstrate that 18-GA zip cord was indistinguishable from high-quality audiophile speaker cable or even the heavy-gauge cables used by the sound reinforcement industry. I was shocked to discover that there were differences, and more shocked to discover that the zip cord performed better than most of the other cables!

Source

When Peter Walker first revealed his Quad ESLs to the audio press he forgot to bring along cables. While his assistants were setting up he dashed out to a local hardware store and grabbed some appropriate cords. He snipped the ends off of, stripped them and connected them. After the presentation many of the reviewers were as curious about the cables as they were about the speakers, thinking that these orange cables they'd never seen before must have had something to do with the marvelous result. And so Walker was queried as to the brand, to which he truthfully replied: "Black and Decker!"

Conclusions?
The most important conclusion I came to doing this test was that my measurement gear is surprisingly repeatable. I'm very happy with that.

Do I see anything that might be characterized as an audible feature due to the different cables in the measurement? Nope. Nada. Zilch. Like I said earlier in this article, this gear is simply not the right kind of tool for the job of characterizing cables. On the other hand, this measurement system is designed to quantify the audibility of certain sound characteristics, and these measurements would tend to indicate the audibility of cable changes is very low. I have to again state my experience is that the changes in the sound I hear with cable swaps is subtle.

Headphone Cable Measurements - Tyll Hertsens

I have absolutely nothing against oxygen-free copper because nobody has been
able to prove to me that it sounds in any way inferior to normal copper.

Philip Newell

Low oxygen copper was created for the windings of large electrical generators (like the utility companies use). It was found that an amount of oxygen (from the air) bonds into the copper during the smelting process. This oxygen causes the copper to become brittle, over time, at points where it is heated (usually from high current flow. Thus the low oxygen has NOTHING to do with sound quality and everything to do with mechanical wear and tear (which is important to the lifecycle times of large, expensive, utility power generators). Further, pretty much ALL copper made now-a-days is low oxygen.

Todd Gearheart