I've recorded a lot of shitty high school band demos and I've recorded a few bands that were amazingly talent and very experienced dudes ready for bigger things.
Maybe if you are doing legit label work 52 weeks a year, it's a given, but in my world the band is responsible for 98% of their sound. I'm talking about the audio quality is almost completely dependent on the band.
I realize that the chain is very important. It starts with the source (the 98% part) then the mic, the preamp, etc. When the source is the same, how much difference does a given mic or preamp make. Well, the mic will give a different vibe of the source. Sometimes extreme, but sometimes not. The amplifier seams to make a much smaller difference.
When I checked out The Listening Sessions I did hear a difference between a number of the preamps. But I didn't ever think that one sound was better. Okay, so there is a dB less at 1K or there is an extra dB at 100 hz. That's never a justification of saying HUGE LOW END. To me huge low end is what you hear in a rap song and if you ran the bass and kick of a rap song into a "thin sounding" pro preamp then you would hear HUGE LOW END. At least that's my guess.
I recently recorded a Beatles on roids type Punk band. I had a 57 and a 421 on the Marshall 1x12 combo. It was a happening sound. I ran it through my Mackie 1604. When we doubled the guitars I ran the mics in the same position into my Vintech 1272. After initial tracking, I labeled the tracks funny and forgot which was which. I still can't tell which track was the Neve and which was the Mackie. I'm guessing you wouldn't either. None of my friends noticed either. If people don't notice, then the difference isn't great enough because the differences between great albums and great recordings is easily heard by the buying public.
I've recorded bad guitar sounds through my Vintech 1272s and I've recorded great guitar sounds through my Mackie. Someone brought up the idea that maybe my preamps are of equal quality. Well, if it's just an issue of quality, then there would only be one preamp... the highest quality preamp. It's an issue of character and I don't think the difference in character is enough to justify the price between the various preamps I have thus far.
The only time I have noticed a difference is in the way a certain mic will react with a certain preamp. Then, it's just a case of an impedence mismatch or something. I just have to remember that two mics can sound similar on one preamp and different on another preamp.
By the way. If a ran a cd line into a API 312 of the big Snoop Dogg hit, I'm pretty sure it would still sound like shit.
Brandon