Pro 'Burn in' time.

[Hifi_swlon]

I trust what I hear, but since hearing is indirect and relies on the brain, it doesn't really provide a way to tell exactly why you're hearing it. I know the 200 and 250pro both audibly vary from my perspective. Whether their sound is always varying I couldn't say. I don't honestly believe hifi is beyond scientific measurement, more simply that most serious scientists are busy doing other 'real' things and the ones working in hifi often have an agenda. Interestingly Devialet probably has the right kit - I'm guessing dcs and meridian and many others with experience in digital audio would too - but it's expensive and so is people's time so are unlikely to be interested!  And all would have an agenda.

My tv picture never noticeably changes. I've never once thought 'dirty power tonight the colours are subdued'. Surely that's something to think about. I'm also a professional in visual imaging so I reckon I'd have a chance to see it.

Anyway I welcome the views - none of us really know what's right and what's not in this area. It's a tricky  one.

[edited to say I would actually be interested in trying some mains conditioning/regeneration but it's hard to get evaluations, and they're big and expensive. And gui your post deserved a better answer but walking and typing on iPhone that was the best I could muster. It was also meant to be very polite if it didn't come across! ]