Is there actually a difference?


Speakers sound different - that is very obvious. But I’ve never experienced a drastic change between amps. Disclaimer that I’ve never personally ABX tested any extremely high end gear.

With all these articles claiming every other budget amp is a "giant killer", I’ve been wondering if there has ever been blind tests done with amplifiers to see if human ears can consistently tell the difference. You can swear to yourself that they do sound different, but the mind is a powerful thing, and you can never be sure unless it’s a truly blind test.

One step further - even IF we actually can tell the difference and we can distinguish a certain amp 7/10 times under extreme scrutiny, is it really worth the thousands you are shelling out to get that nearly-imperceivable .01% increase in performance?

Not looking to stir up any heated debate. I’ve been in audio for several years now and have always thought about this.
asianatorizzle
The challenge with tests is that the testers are in an unfamiliar room, with unfamiliar gear, and unfamiliar music. It's overwhelming and in these conditions SPEAKERS can be difficult to discern. 

Slip a new amp into my system, in my room, and with my music and I'm going to notice the change.  
I am firmly in the "Yes, they can sound very different camp." In the past, I have switched out similar mid-fi amps on lower resolution systems and heard no discernable difference, but since I have had better systems, any amp that I use now sounds distinctly different. The differences are easy to hear, simple as that.
Every type of capacitor, every brand of resistor, transistors, tubes, all sound different.

Add circuit topology, and, while there may be similarities, no two amps will sound identical - that is, with practice and attention.

I change one thing at a time in my DIY Class A SS; sometimes it takes a day or two to educate the ear, but most changes are audible. For example, as an experiment, I used different brands and types of resistors in a high quality rotary switch as the gain resistor. The differences were obvious, the choices clear - and the most expensive resistor made the poorest sound.
System synergy is most important. There are big differences in sound between a good tube amp and a SS amp. I also disagree that all good SS amps sound the same. IMO, there are a lot of SS companies that have a HOUSE. For example, classe and McIntosh have warmer sounding amps where there are companies that have more cooler sounding amps.
Those who can't tell the audible differences among amplifers are lucky and with more money in their pockets but should get their ears checked.