This type of thread tells me that unless we are electrical engineers or acoustic engineers, according to the item, it is almost impossible for us non professionals to understand if the gains are real, or if we are being sold snake oil.
We have a see of online consumer HiFi magazines, that I often feel have an unhealthy relationship with the vendor of the item they are reviewing. A headphone I was interested in was given a glowing review in a major HiFi mag. Elsewhere, and on user forums, it is considered a major failure, sounding far worse than the previous model. The Grafite cones, which I am pretty sure offer no benefit after reading various technical publications, were given exaggeratedly positive reviews in a couple of publications. Oh! look, the reviews have been included on their site. Did money change hands?
Why did I buy a ā¬40 (reduced from ā¬80 in a closing down sale) USB cable to connect my streamer er to my headphone amp? It is very pretty. What was wrong with the one savaged from on old printer. How about the cheap USB C cable that connects my portable HD to the streamer? Binary numbers have no sound just 1 or 0 values.