You are right ...
But we cannot hear without an aural memory biases set, trained or untrained, engrammed in the body metabolism and not only in the brain ...Our focussed attention is like a children on the back shoulders of our giant aural memories history so to speak which walk always with us ... Even babies had one in the womb ... the focus of attention is not born from a virgin without father so to speak ...😊
It is because of these trained set of biases that musicians can beat more than 10 times the Fourier limits or Gabor limits about signals localization between frequency and time ...
Then supposing an ideal pure "sound" out of any biases is preposterous and an ideological proposition by objectivist crowd ...
By the way placebo does not means deceptive and illusory as in the vocabulary of the objectivist, in the opposite placebo work on the same neurological locus than a drug on the nervous system to help the self healing process ...It is a fact in medecine ...
Then using placebo concept as an illusion or aside effect compared to a real drug is a simplistic ideology or an interessed bias to favor and /or prove statistically that a drug can be effective or not ...Placebo is a very complex concept used by mothers , wise doctors, publicist, but also statisticians in the drug industry or any other industry etc because it work really as a drug work and must be eliminated to asess the power and effectiveness of other contributing factors as a drug etc ...
In the same way the sound qualities are perceived in the context of an aural history ... We can artificially disconnect this aural memory from the direct momentaneous sound experience but it is artificial and did not disprove the existence of a perceived quality always and in all case ... It just put them aside for the ideological standpoint that allege that sound quality are ONLY subjective biases that must be eliminated ...It is not even wrong ... And it is not right either because sound qualities may also convey objective information as qualia ... Then blindtest dont tell all the story there is to tell about sound experience...
When audiophiles perceive audible differences where non exist in casual non level matched non time synchronized comparisons it isn’t due to a placebo effect. It is due to how we hear, process and remember sound. We can not effectively compare an aural memory to real time sound. So while it may seem the same as a placebo it is not. The aural memory is incomplete and was filtered by steered focus