But do you mean that the appearance of the amplifier, or the finish of the speakers is a valid part of the performance of the equipment? I imagine that if I am presented with a huge amplifier made of platinum and marble that costs $1 million, it will affect me at a "spiritual/emotional" level even if, unbeknownst to me, inside it is a mid-fi Japanese circuit board. The objectivist would, at least, attempt to eliminate the peripheral aspects from his assessment of the performance. The subjectivist would not.
The subjectivists appear to be telling us that they embrace the emotional impact of price and appearance; they are all aspects of the perceived performance of the amplifier. I suspect that many objectivists don't realise this, and dismiss the views of subjectivists as being those of people who don't realise they are prey to expectation bias when, all along, the subjectivists are actually embracing the expectation bias.