Not sure how long many of you have been in this game, but the basic performance here would have been regarded as pushing state of the art forty years back. The HiFi Choice amp test books regarded basic distortion levels of -70 to -80dB as pretty much excellent and IMD (19 + 20kHz) of 60dB wasn't sniffed at either. So called reference products (often valved) with distortions in the -40dB range were highly recommended and a certain high end qualified techie 'guru' reviewer who should have known better consistently put it about that measurements played no part in how a piece of high end equipment 'sounded.' - I'm thinking C-J and ARC confections of old. Mind you, he had a reputation as a burgeoning high end 'go-to' reviewer status to consider back then I felt.
It's great to see the above figures bettered so easily these days, but I would ask for caution as regards chasing (inaudible?) numbers here. I was told years ago that our brains processing of visuals is around 70% compared to auditory and again if you can cast your minds back before home theatre systems came along, how we put up (and still do) with truly ****** sound from our TV's which was tolerable purely because we had a picture to take most of our interest. I suspect that's why tech performance of these AV products is so old fashioned in terms of distortion and so on, as the end user almost certainly wouldn't ever notice it. Hopefully reviews like this will lift the lid on such attitudes.