Dog- Great question! I think the best any of us can do is make an educated guess about the weak link in a system.
My approach is to read the forums carefully for a long time-- year is not uncommon. I look for components that get very strong review from the media and AG members, in particular, those members I have come to know and trust. I also look for clues regarding system synergy. What this does is increase the likelihood that a purchase will result in a system improvement.
As far as PC's, the improvements I have noticed have been with respect to dynamics and cleaning up the upper frequencies. Relief from listener fatigue and sweetening up strings.
Over the last 10 years I've only made 2 purchases that disappointed me. But I am getting to the point where it is probably going to become more difficult to find things that are truly better, not just different.
My approach is to read the forums carefully for a long time-- year is not uncommon. I look for components that get very strong review from the media and AG members, in particular, those members I have come to know and trust. I also look for clues regarding system synergy. What this does is increase the likelihood that a purchase will result in a system improvement.
As far as PC's, the improvements I have noticed have been with respect to dynamics and cleaning up the upper frequencies. Relief from listener fatigue and sweetening up strings.
Over the last 10 years I've only made 2 purchases that disappointed me. But I am getting to the point where it is probably going to become more difficult to find things that are truly better, not just different.