In industrial use, Power Factor Correction (PFC) is achieved by programmable AC sources, very simply put a frequency generator for high power. They are used when the AC varies a lot and/or low distortion (THD) is required for example, a lab or medical devices.
PFC units were wide spread till the 80s when clean power was universally available. Not quite sure why Meitner needs one. Anyway, different ways to skin the dirty power cat.
In the recent years, I have done quite some read up and consequently, testing with power conditioning alternatives. Active ones such as the PS Audio P10 is pretty darn good but sounded solid state IME so I prefer the passive ones like BPT but more so Audience adeptResponse (YMMV).
A year ago I acquired one of the Elgar
Ultra Precision Line Conditioners. The 6006B (10A) model can be found used on Ebay; the larger, 3006B is highly recommended by Ralph Karstens of Atmasphere and probably not a easy catch and you need to have the space to put it. In short, the 3006B consists of a double-shielded isolation transformer providing most of the output (70-95%), supplemented by a correction circuitry to achieve a near perfect sinus waveform (<0.2% THD per their brochure!). I am using this front ending the passive power conditioners, iow the adeptResponse that I have in my systems are fed from the Elgar 6006B in the basement (the fan operation is loud). I would say a small increase in clarity and texture, maybe because I have dedicated lines.
I believe some here on the Gon use an isolation transformer between the box and wall outlet / conditioner with sonic benefits. The Elgar has one built in.