Fosi Audio V3 op-amp rolling, has anyone tried it? Snake oil? Or are there actual differences?

[solderdude]

As always what is missing is - the listening tests. What individual people hear - is what they hear.

of course, but that is not the problem. What one hears is what one hears. The problem lies in HOW to properly test (using the ears) under equal circumstances.

For instance... swapping op-amps (knowing what's in there) and comparing from memory is almost guaranteed to hear differences. Regardless if the differences are caused by the different op-amp or from other causes.
The ONLY valid way, if one REALLY wants to know, is to directly, level matched and properly controlled and statistically valid comparison between 1 amp with original op-amps and with 'upgraded' op-amps.

Let's face it... proper testing is a LOT of work and very time consuming and even exhausting. NO V3 owner is ever going to do that. Instead most people that believe in op-amp rolling just put in a more expensive op-amp or a recommended one on the premise that it'll sound 'better' and give it a listen. They will certainly like it and hear an improvement (it is rare to see people preferring the original op-amp). Maybe they even put back the original ones in to 'verify' it sounds less good than the new (expensive) one they put in and quickly change it out again for the newer one and voila... there is the good sound again.

That's how it works. The fact that no controls are used is what most ASR folks have issues with. Most of them may have never done extensive and properly controlled blind tests themselves by the way.

To insult what people hear and tell them they are deluded etc. etc. actually says a lot of those who repeatedly make these insulting comments.

I understand that's how it 'feels' when someone 'reports' they (clearly) hear differences.
However, that works both ways. People that actually know about proper testing and 'op-amp' sound are equally insulted by folks insisting they have it wrong.

No one in their right minds would deny that measurements reveal the outcome of the chosen layout and components and the mentality of the teams that created the piece of equipment.

Measurements say nothing about the layout and components nor the mentality of the team(s) or individual(s) that created the product.
Measurements (when done correctly and all required ones are made) can say everything about technical performance, specifications and signal fidelity.
It does not say ANYTHING about how someone 'hears' or 'perceives' it at home, on their gear, in their listening conditions with their transducers.

The fact remains that the important end point is - does the individual like what they hear.

Yep, your only valid point so far. This, however, has no direct relation to technical aspects.

This is as always defined by the sum total of that individual's life experience/cultural brainwashing For some time now a lot of people have damaged the ability of their pathway to hear - their ears, to transmit an accurate route to the brain and it's ability to provide even remotely something resembling the music that entered the aural pathway.

What a strange description of 'hearing'. It seems your reasoning is heading down south here.

Note: The distortion and frequency response is determined solely by the TPA3255 + filtering + power supply. The performance of the op-amp (in x -1 gain mode) is vastly exceeding that of the following class-D stage.