Best way to A / B test amps? Use a switch?

I still think the audiophile thinks his aural memory is much keener than it is and not susceptible to audio forum interference/influence.

Oh no. How? How could that possibly be the case? Only if maybe someone popped out of the womb and straight away started churning out Fremer-level reviews. Which no one ever did.

We all had to learn how to hear. We all struggled to attain whatever level we are at. For sure that was the case with me. Go read through my posts, you'll fine a whole bunch saying this same thing. Several long ones recount how it took me one full year just to learn to distinguish good DAC from bad CD. Then about another year developing that same skill to a level where- cones, footers, cables, elevators, fuses, panels, on and on-  it seems there's no end to the things that matter. 

And I don't need to match levels, or play the same track twice, or switch fast, or any of that. Which is by the way not bragging nor BS nor even all that unusual. The dealer I learned from never once played the same track twice, and Michael Fremer is somewhere on video saying, "I know some like to do that but I don't." 

That's not to say it can't help. When learning any sport- racquetball, golf, autocross- what's the first thing the coach always has you do? Practice. Break it down to some dumb little part and do that one little part over and over and over again until you get good at it. 

Which, let's face it, nobody very much likes. Well, sorry. Too bad. I mean really, its just too darn bad. Truth exists, and whether you like it or not the Truth is you never get good at anything any other way than by doing it. A lot. 

You want to know the truth? The truth is this fact is so well known I think every single one of us knows this very well. We just would rather delude ourselves and make excuses for our shortcomings, because this is a whole lot easier than admitting the shortcomings.

But hey, your life, your choice. You can make excuses. Or you can do the work.

Choose wisely.

Everyone knows it’s BY FAR better to A/B test with instantaneous switching than relying on memory and what you think you heard.

Well, no, that is not the case at all.

First of all what you suggest is impossible. Even instantaneous switching still the goal is comparing. With what? With what you heard. When? In the past. Where’s the past? In memory. Nowhere else.

You simply haven’t thought this one through. Not at all.

Which aspects of the sound? Well how do you even begin to answer that one? By thinking over the different aspects. Which involves what, again? Memory.

All you’re doing with this instantaneous switching malarkey is moving the proverbial runner halfway to the finish line. You know the story, right? To get to the finish line he must go halfway, then halfway, then half of that.... never gets there. When in reality, WHOOSH! Right on by.

That’s exactly what you’re doing. Inventing some nonexistent constraint, insisting its real. When in reality, WHOOSH! Right on by.

Besides, what about warm-up? Break-in? Acoustic treatments? What about differences between recordings? Do you now require duplicate identical turntables just to decide which LP is better?

Its really just beyond silly.

Especially since, if the difference isn’t big enough you can still be sure after the 5 minutes it takes to change something out, then why would you care anyway? Answer me that one.

I would have thought there was something practical on the market already.

Well, there would be. If it would serve any purpose. Which it doesn't. So its not.

But seriously, the question stands: If you can't be sure after a few minutes then why do you care?

I believe that the mind forgets what it heard 5 mins ago and internal biases kick in strong.

Yeah, my head was once stuffed full of this exact same nonsense. True story, I drove 200 miles to a store to compare interconnects just because they had this device that allowed you to switch back and forth instantly. Yeah. So I drove 200 miles to hear for myself.

Only when I got there, owner says sorry, we had to send it back. But you're welcome to compare anyway. And showed me the amp and let me alone.

So I listen to his interconnect a few minutes. Okay. Whatever. Flip the source. Swap interconnects. Flip the source. And.... WTF!!!! I mean WTF!!! Thought for sure I had messed up this guys beautiful expensive tube amp. Could not cut it off fast enough. What the.....?!?!? Everything hooked up right. Well then.... what?

Gradually it dawns on me. The freebie patch cord I had brought along to compare sounded so awful it was obvious instantly and from behind the speakers. Turned it back on, sat down, forced myself to endure what I had been playing and enjoying every night for years. Could. Not. Believe. It.

But hey, if you believe you forget, I believe you. Can only imagine how many fights you must get into with your wife, never being able to recognize her voice on the phone, but hey, I believe you. Really. I mean, that is after all why they have Caller ID, right?