Q2.1 Which amplifier should I use? Which cable?
Answer: These are very hard to answer since each reputable high end manufacturer produces products with merit. I wish there was an amplifier with the swinging rhythm of the Naim amplifiers, the silky midrange of the Audio Research, the bass authority and control of a Krell and the overall "rightness" of Mark Levinson but there is no such thing. You must listen to as many different amplifiers as you can and take notes in a little notebook as you listen. Eventually you will reach some conclusion that both your head and your heart will agree to. The one thing you can be sure of is that whichever amplifier you use you will hear everything they are capable of through a Duntech speaker.
As far as cables are concerned there are a vast number of schools of thought. These people all have their own arguments (some of which actually make sense!) but in the end you have to listen to them. Make sure you are certain because the resale value of cables is negligible. In some cases, such as Naim Audio, they sell cables designed to work with their equipment. I would never consider using someone elses cables in such a case.
Q2.2 Do you believe in tweaks?
The issue of tweaks is really difficult to address. Just because the explanation for why something works might sound half baked, the tweak may actually work all the same. In such a case it may be that the designer himself may not know how it works. The one thing I want you to hold in your mind like a mantra is this: "Just because it sounds different does not mean that it is better!". I evaluate our new designs for months, both at home and at the plant before I am sure that they are as good as we can get them. A small change here or there can alter what you hear in a beneficial way on every piece you listen to until you hit that fateful one which shows the change for what it is. Even your mental state can change what you hear. What I hear while I am making breakfast in the next room can be more exhilarating than what I hear in the sweet spot after battling through traffic to get home in the evening.