<font color='#000000'>Good golly, Mr. Vivaldi! Didn't mean to put a bee in your bonnet!
The comparison of musical instruments and amps is, as I'm sure you'll realize, not quite valid. Not even for electric guitars. Pickups, being small microphones, are highly variable for one thing. Not to mention the varying acoustic and mechanical properties of an electric guitar's or any instrument's construction and design. I'm a musician myself, a percussionist. I know a good drum or cymbal from a bad one, believe me. On the other hand, an amp is a purely electronic device.
My belief is based on the fact that decades of research in electronics, psychoacoustics, and related disciplines have failed to find reliable evidence of audible differences in any two amps -- in fact, any two purely electronic signal paths -- that have flat frequency response across the entire audio band, low distortion, low output impedance, and low noise, (which pretty much describes every competently designed solid state amp these days) in a properly done blind test at
matching levels. (Even back in the early 70's it was pretty much a given that all good amps were pretty much alike in sound -- but not all amps back then were necessarily good!) It's the matching levels that trip us 'philes up, even when we try to a/b test. Trouble is, matching two amps to within that tiny tolerance is a tricky, time-consuming affair even in the lab with the proper equipment. Small level differences down to about 0.15dB (0.1 is preferred!) are perceptable, and the louder amp even at that small difference is percieved to be "better". This phenomenon is well known and documented.
So we mere mortals are easily fooled when we plug in our shiny new amp, load a favorite disc and breathlessly press "play"; if it's a tad louder of course it sounds "better". Even to the disinterested party in the next room. Not to mention the fact that we spent a fair chunk of change on it and are flush with the excitement of our new toy. Lots of bad mojo at work if you're trying to be unbiased!
My mantra is: people are easily fooled, even by themselves. Science is the best defense we have against this. Even if it isn't perfect!
Actually, I replaced my old amp this past year. The new(er) amp (actually, I bought it used) sounds nice. It might even have sounded better. Hey, I can't deny there's been progress since 1972! But frankly, the main difference was that the new one is 100w/ch and the old one was only 60. So I didn't have to turn up the volume as much. Might be a tad cleaner. But my new speakers made a hell of a lot more difference*. And anyway, I'm not a hermit. I have heard a fair number of other systems besides mine! But yeah, I'm not into equipment churning. I keep stuff a long time. Drive my cars into the ground, too. I'm admittedly a cheap b******.
On the other hand, I know what live music is supposed to sound like and can still hear fine differences in sound both live and recorded. So I ain't deaf yet. My wife would beg to differ but that's just "selective hearing" at work. A survival adaptation of the male of the species
Of course, this finally becomes as much about world view and personal philosophy as anything, like believer vs. agnostic, vegetarian vs. omnivore, Mac vs. Windows. So, recognizing that, can we all just get along?
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*Boy, talk about bias: I built them myself. I'd probably have a hard time saying they were crap unless they made crackling sounds and gave off smoke! But they are actually awfully nice even when I try to be objective. No, really. Even "She Who Must Be Obeyed" says so.</font>