Maybe. Except that there are things we cannot measure.
@donsachs That was true back in the 1980s. It really isn't now. Measurement technology has really advanced in the last 40 years!
Its the distortion of any amplifier that is its 'sonic signature'.
There are many class D amps I've heard over the years that I had to struggle to take seriously. But I've heard some now that sound every bit like a very good tube amp; just like in a tube amp where arcane subtleties can make or break a design, the same is true in class D (or any design for that matter). I pointed to what is needed to make a successful amplifier (if you're going to use feedback) in my prior post. Most amps using feedback fall short of the GBP needed so distortion is much higher at higher frequencies than the THD measurement suggests!
THD by itself, if that is the only harmonic distortion metric used, allows a lot of problems to be swept under the carpet. When it is the sole metric, it leads to the myth that 'there are things we cannot measure.' The reality is if the harmonic spectra is measured at several frequencies (including above 1KHz) and if distortion is graphed vs frequency, then we start to be able to predict the 'sound' of the amplifier.
Both the 'measurement only' guys and the subjectivist guys hate this! But Daniel von Recklinghausen was right- if it measures well but sounds bad, you measured the wrong thing.
I’m convinced that no feedback plays a role as every amp I’ve heard with feedback doesn’t have that super inky back blackground or perfectly rendered transients.
@cloudsessions1 That is because in most amps employing feedback, its poorly applied- so my surmise is you've yet to hear one where the feedback was really right. Norman Crowhurst pointed this problem out 65 years ago, describing how the feedback node (the point in the amplifier where the feedback signal is mixed with the incoming signal) isn't linear; therefore the feedback signal gets distorted before it can do its job, thus creating higher ordered harmonics that have given feedback a bad rap. Its not the fault of feedback so much as poor application. Amazingly, little has been done in the last 6 decades to fix this; IMO mostly out of ignorance and a lack of will to do so.
I've heard amps with very high feedback that sound utterly relaxed in the mids and highs and portray depth with ease.