Without ever really thinking about it, I had always assumed that the companies that "make" their own strings actually manufacture the core and wrap wires.
They don't...
They only do the wrapping...
(https://i.gifer.com/QwbL.gif)
After I "discovered" this, of course I started search for who makes the core piano wire and ran across this:
https://www.ken-tron.com/news/music-wire-instrumental-strength-required/
It was published in 2017 and states:
"If you were playing your guitar today or if you heard a song with someone else playing a guitar, there is a pretty good chance Ken-tron Mfg., Inc. was involved.
Since the early 1980s, Ken-tron has been a major supplier of music string wire, primarily for guitars.
Until recently, most of this wire was known as wrap wire."
...
"At the request of many of our music string customers, Ken-tron recently made the investment required to begin production of guitar string core wire. This is the wire that makes the bare, or unwrapped, strings as well as the center, or core, of a wrapped string on guitars. This wire is a steel or plated steel wire."
Anybody noticed a difference in their strings in the last couple of years?