But i dont like when people apeak always of "placebo effect".... An incremental series of positive changes accumulating in months cannot be illusory....On the contrary. Believers in homeopathy become more and more convinced over time that their water has healing properties. They seek confirmation biases and use them as ‘proof’. We see it all the time, even on this forum. In a life of 70 years there will be nights of good sleep and nights of poor sleep. Put a box and a cat under your bed, and when the next night is a good sleep then that is due to the box. And the cat. Or the cat. Or maybe the effect of going to bed convinced you are going to get a good nights sleep. Or random chance.
I watched Synergistic Research’s own video demo of their HFTs. Untreated room, level 1, 2, 3 etc. They never said “you can’t tell with a short listen”. They said each time there was obvious change, they described the change and directed us to it, and that we could hear it over a video quality feed with poor recording. You know I’m a skeptic but even I wondered if I could hear a difference when the salesman directed me to a certain sound after a ‘change’. So I asked my son to take the audio stream and run it in his LogicPro tools at a resolution far higher than the original broadcast. We chopped out the repeating music played at each level of the test and anonymised the samples. We shuffled the order to blind each other. We placed them as tracks so we could switch between them for hundreds of listens. There was no difference between them that we could identify when there was no ‘direction’ from the salesman, and when there was no self-direction from knowing which sample was which. Those ‘changed’ sounds we were directed to by the salesman were, you guessed it, there in every sample. It wasn’t that we couldn’t identify which type of sound went with which level of treatment - we couldn’t hear or see any difference at all when blind. Of course, if he switched to vinyl, or switched the speakers, the differences would be huge.
I’m aware of some of my own biases, and unaware of course of others I have. Maybe I wanted not to hear difference. So by zooming in to the frequency responses in great detail, the patterns were, physically, the same. Maybe I should post them here.
Just like the cup and ball trick. Avoid the misdirection of the magician, and avoid your own biases, and you might get to keep your money. We never do though!