The engineers argue about numbers, the tweakers argue about sound. Neither side has a pot to piss in.
Here's the deal: First most women, and some men, are genetically incapable of hearing much difference between amps and speakers. Good for them! They can enjoy music and not give a heck about all this audio stuff! Because it just doesn't matter to them. And we shouldn't be beating them over the head about it; let them have their ipods and compressed music and be happy.
No, I'm not being chauvinistic. It's just an observation. If a whole bunch of women want to write me and tell me that audio matters enough to them to spend thousands on really good amps and speakers, I'll change this. All I know is I can count on the fingers of one hand the female members of tube amp forums world-wide, and I know for certain there are hard-wired differences between the neurology of male and female brains. There does appear to be a difference in psychoacoustics for men and women, which I will do a literature search on someday to back up this outrageous statement of mine (it actually comes from reading some psychoacoustic literature somewhere, but I don't remember the source right now...I'll find it.)
Second, for those of us who can hear the difference, nobody yet knows how to measure that difference in a meaningful way that will correlate with the discerning listener's experience.
And here's why: blinded AB comparisons are absolutely MEANINGLESS.
Yeah, that's what I said. Blinding and double-blinding in science isn't always the right way to go. Psychology has known this for decades and decades. More on psychology later; suffice it to say that some of the best psychology tests have been purposefully designed to trick the subject, and blinding had nothing to do with it.
Why? How come do I make such an outrageous statement?
Because we listen with two different parts of our brains: we use one part when we don't know the source of the sound, and we use the other (the one that appreciates critical differences in sound quality from stereo systems) when we DO know the source. I'll explain in detail later. Right now, I just want to plant this startling idea in your head. No, you're not crazy. When you know which amp you're listening to, you CAN hear the difference, you're SUPPOSED to be able to hear the difference. Blinding you only means that the part of your brain that cannot distinguish will be put in control, and thus the blinded test becomes meaningless.
So, the objectivists and subjectivists can argue till the cows come home, but they won't get anywhere, because there's no way to prove either right or wrong until we figure out how to do meaningful listening tests without blinding. Tricking? Yes, probably. Blinding? No.
Does linearity in an amp matter? Yes. Do tube harmonics matter? Yes. Both are true at the same time. If they weren't, we'd just all go buy transistor amps at Radio Shack and live happily every after. But you know that's not the case - at least for you.
Criminey, I wish I could get this italics to turn OFF!
I'll eventually get this nailed down, and when I do, I'll put it here, and then we can finally make some sense to all this madness. Until then, have faith in good design, and at the same time trust your ears. And don't let anyone draw a curtain and challenge you to tell the difference - it's like comparing apples and elephants, that's how different it is.
It's no accident that back in the 30's they used to "prove" how good their amps and radios were by drawing a curtain, and then challenging the audience to tell the difference between live music with live musicians on stage versus recordings through the amps or radios. It was a meaningless demonstration, against all common sense - the wrong part of the brain was engaged, and Toscanini himself could not have told the difference.
Here's what I think is going in, in very general terms. Like I said, when I get a chance to really get into the psychoacoustics of this, I'll put it here. But I've studied enough science and scientific literature over the years that I know when something is true...or mostly true. It may not be so simple as I'm about to describe, but I believe the basic principles are correct:
When we were evolving as a species...our closest relative before the apes is this little tree varmint...at some point we evolved two...or at least two...different brain centers for processing auditory information.
One center, probably the first, was for recognizing a sound as dangerous - and instantly triggering the brain into fight, flight or freeze mode. To the extent that we had cognition - cerebral cortex function - we might consciously decide whether to fight, flee like heck, or freeze silently...or perhaps there was even a fourth: play dead.
Have you ever seen a possum play dead? It is the darndest thing. Once, when I was walking in a forest, I heard this tiny little shriek and rustle in the leaves to my side, and when I stopped and looked - I had to look hard, it took a few seconds for me to see the little guy - there, twisted on the leaves, his pink tongue hanging out, was a dead possum. Well, playing dead. I had startled him, he had given his little death shriek, and then had fallen down in a position calculated by him to be as close to dead-looking as possible. It was a dramatic tour de force. (DreamWorks Pictures/Paramount: Over the Hedge: got it almost perfectly right; of course, possums don't walk on two feet and twirl around to fall
dead...)
I quietly stood there and watched him, and after a considerable space of time he lifted his head, looked around, got up, and rustled off without a backward glance. To this day I don't know if he actually saw me; perhaps possums are programmed to see movement more than outlines; another thing I'll have to eventually look up!!
Actually, there's a fifth possibility for this brain center, I think: ignore. Not a threat. So, we evolved with this brain center whose job it was to keep us alive by listening - processing incoming auditory information - for threats. It would memorize threats, that's important. It would memorize non-threats, that's also important. But what would it do when it wasn't sure what the source was? Latch onto it, that's what, and not let go until it had it figured out.
If the sound wasn't TOO scary, what would this little brain center, our little protector in the night or in the bush do? It would get us to sneak over and LOOK, that's what it would do. Once we saw what the source was, and decided it wasn't a threat, then our little auditory protector would stick it into the "recognize and ignore" file - or "recognize and EAT" (a sixth category) - freeing that sound up for aesthetic considerations later. And, while I'm here, I can't help but point out the obvious: when our little protector wanted to find out what the source of the unknown sound was, what sense was recruited? Hmmmm??? Sight. Get it?? Blind our little protector, and I'll bet it hangs onto sounds like a pitbull on a bone; ain't none of this gettin' up to the snooty center, the aesthetic center!
OK, you say, well, music is non-threatening, so this lower brain center should leave it alone, pass it up to the higher center that has aesthetic discrimination, right? Ummm, not so fast. When we are listening for differences between audio components, we have an emotional investment in choosing the best one, right? But, if we don't know which source we're listening to, even though we consciously know it is music...and not a threat to life (just our wallet!
)....this lower brain center recognizes the emotional involvement - the danger of getting it wrong - and takes over. Heh heh heh. Little dickens. 
Now, the function of the lower brain center is NOT to distinguish which sounds better - that's the function of the higher center, probably in the cerebral cortex - no, it's function is to IDENTIFY the source of the music. And that's precisely what it's going to do, come heck or high water. So, a blinded AB test might...might...be useful in you helping yourself to distinguish between sources...but it won't help you in making an aesthetic judgement about which you like better, because the information is being held hostage by the lower center, and the aesthetic center is not being given the information...or the control. Maybe...just maybe...once you've taught yourself to reliably tell which is which while blinded....then maybe you would be better prepared to remove the blinding and make a correct (for yourself) decision on which sounds better (to you).
So, until a good research psychologist wants to play with this, maybe join forces with me, and figure out how to make aesthetic judging of amps and speakers and cartridges, etc, etc, reliable and correlatable to electronic measurements, WITHOUT BLINDING (but tricking is perfectly acceptable, if it tricks the lower center into letting go), I suggest you KNOW what source you're listening to, know the specs of each, and then, putting it all together as best you can, go by Duke Ellington's motto: "If it sounds good, it IS good."
I'll bet if you listened to a good SET amp side by side with a good PP amp, each matched to the right speakers, with the right music for you, and you knew which was playing at each moment, you'd be able to tell which one you like better. (You'd probably like both for different reasons). If you can forget everything you've been told as gospel truth, and just listen....
Your Moment of Zen for the day. Best, Charlie
P.S.: It should sound good sooner and later. Don't get tricked into taking home something that doesn't sound good to you right on the spot, with the assurance from the "expert" that, after you listen to it long enough, you'll like it. Uh Uh. That's accomodation; a subject for another day. Now, is it possible for something to sound good at first, and then not so good as time goes by? Welcome to the world of being an audiophile!!
This is a universal experience among those who can discriminate between good sound and bad sound. The longer we listen, the more flaws we hear. The tiny moments of clipping on very short transients we didn't notice at first. The increasingly annoying intermodulation distortion that muddies up the image. The moment of "blocking" when the output stage loses it's bias on a crescendo or big transient and you miss out on the best part of the whole finale. The floppy bass that seemed fine in the show room, but after a month at home, we really miss the clarity of what Ginger was doing so perfectly behind Clapton and Jack Bruce. But this is yet another blog subject for another day; let's just say, now you know a little something to think about.P.P.S.: Be very afraid of a wall of speakers and a huge master switch in the salesman's hand. First, you don't know which set has been optimized to sound the best THAT day: ("Hey, Mikey, we gotta unload more of these bottom-of-the-line Infinities; set up the amp so they sound grrrreat!!). Second, heck, you don't know for sure which speakers are really on, half the time. Yeah, you can run up and double-check, but that gets old real quick. And annoying as heck to the salesperson, who is about NOT to be your friend. Third, is this the way you'd set up your speakers at home? A wall of speakers is just like cutting holes in your walls at home and sticking the new speakers you just bought into those holes. Right? Think about it. No, you really only have two choices: audition stuff set up perfectly in a dedicated room - either at the dealer or at someone's home - or learn a whole lot about speakers and amp crossovers and amps, and DIY it! Yes, you CAN make your own speakers and figure out how to make them sound fabulous with YOUR system. Sigh...yet another blog. Or just check my links; treasures there. On the other hand, there are tried and true models that are famous for working well with particular setups. Do you have a SET amp, not so many watts? You might want to check out used Klipsch Horns, just find out the right model. I'll put the model's here when I get a chance to look them up. Do you have a medium-power PP amp, with great output transformers? You might just want a set of old AR's, you'd be amazed, especially if you had Rod Elliot's (see links) Crossover Card in your amp and separate Woofers. I once had AR's, I forget the model, it was about 1971(?), back in Backbay Boston, and, until they FRIED my Heathkit Transistor Amplifier (a mad detour into SS land I soon learned to regret...of course, the AR's tendency to have impedance dips at certain frequencies that draw huge current from the amp didn't help), they were simply astonishing.
I also years later goofed with a Sansui Mosfet amp...I know at least one other tube amp builder who made THAT mistake...you could never figure out what was missing, but SOMETHING was definitely missing (a tube!). Someday, maybe I'll try to put a list together of great combo's, amps and speaker combo's that DIY'ers know from their own experience sound darned good. Doesn't guarantee a match for you, but it's a lot better than nothing. I wouldn't take my wife's word (or your's, for that matter, no offense) on the sound of a stereo system on a bet, but when DIY'ers have a consensus on a particular match-up, it's usually the result of good ears hearing good things, with the acoustic aesthetic center of the brain well-engaged.
