Always an interesting argument, paper graphs vs. ears. I have sold high end audio and had a company selling and installing high end systems. The brands I have sold or were the dealer for were JMLab/Focal, B&W, Maggies, SoundLab, Ayre, AudioResearch, Acurus, Aragon, YBL, Wadia, PS Audio, NAD, Rotel, PSB, Harbeth, HSU subs and quite a few others. I also have an Associates Degree in Electronics so I can understand a lot of how circuits work. And I can solder. A lot of theoretical Engineers can't. My point is, I have heard and compared a lot of different brands and models for a living, and I liked my job. I have made my own interconnects and since a lot of my systems were in-ceiling/in-wall stuff I even bought 15 different volume knobs and tested them. BTW, Knoll's resistor based knobs sounded the best, way better than pots.
So yes, Virginia, there is a difference in amplifiers. I sought different audio gear and interconnects because of their differences. Because people hear and gravitate towards a particular sound/flavor. That's why there's not one generic box that says AMP on it for everybody. I think all of the brands I sold were quality, but they did sound different. Probably because I played shred guitar for years I like the sound of tubes. On paper they may not spec well, but the most sound I've gotten out of paper was shaking it. There are a lot of fraudulent or misguided attempts to enhance sound quality but I've seen some weird tricks that work. One is big ass AC cords-12ga. high strand count cable with hospital (Watt-style) connectors. After running the electricity through miles of Romex why do they make a difference in the sound through speakers? Doesn't work on some systems but my AR LS-8 and Aragon 8008BB appreciated them. Personally I really liked the Aragon amps, especially the 8008 series. And yes, they sound great with a non-balanced pre. I like tube pres myself, but that's just me.
So my job was to listen and compare and then present my recommendations to the customer based on qualifying questions like their existing gear, room environment, tastes in music and so on. If you do something for 20 years you should get good at it. And for every customer I had to prove to them there was a difference, an improvement or no sale. Depending on reviews only sucks, I trust my ears to know what's good (for me, anyway).
To wrap up a long-winded conversation: if you can find a high end shop near you and if they're a 'good' shop they'll work with you. Sometimes audio repair shops will carry used and consignment gear. If not check out reviews from good audio mags like Stereophile (I hope they're still around) or the like. CNET ain't gonna cut it for good audio but I do like their TV reviews (I'm ISF trained). Manufacturers sites usually archive reviews on older models as well.
You are going to get a lot of recommendations. Opinions are like... bellybuttons... (polite version), everyone's got one. Since this is a long term purchase take your time. Join an audio-enthusiast club if there's one nearby or post a c-list ad in 'electronics' and start your own. I used to attend monthly meetings at members houses to hear their systems, listen to mostly good music and geek out about sound and motorcycles (lot of members also rode). Enjoy the hunt, most of the above recommendations are good ones.
