ASR seems to have the supposition that people buy a power plant to ‘cure’ power problems. I think the reality is that genuine power problems aren’t terribly common, and that one may not know if they had a power problem until a powerplant (or similar) was tried in their system.
I would guess that many/most buy a PP not to cure a problem, but simply to see if it increases the sound quality of their hifi system.
I live in an industrial area, and have solar power. I’ve always assumed my power supply might not be optimal, though several passive conditioners I’ve tried have had no positive effect whatsoever, and have made amplifiers worse.
Having used a PP12 for the last few weeks, Its become apparent that my areas power supply is pretty great, compared to reports from other PP users regarding THD etc.
I have 3 phase power available, with 2 of those phases available in the hifi area, and have 230v supply.
Phase 1 is usually 240-243v, with around 1.3% THD in the day, and increasing to 1.9% at night.
Phase 2 is usually 248v, with THD around 1.2-1.4% day or night.
So, apart from a higher than optimal voltage, pretty good from a THD perspective.
I mention all this as preamble to say that despite having a very decent supply, improvements are clearly audible using equipment revered by ASR, such as the Topping A90, and Genelec 8341’s. Specifically, given that ASR carried out measurements using the A90 to show that there were no audible differences, I thought that worth mentioning.
The differences aren’t night/day, and don’t change any fundamental character of the system, however once heard it’s not possible to willingly go back to NOT using a PP.
As an aside, even at deafening volume, the PP12 reports that current draw is less than 100w for the complete system, which given each 8341 has 550w of amplification is lower than expected.