Tboooe,
I have to disagree on your comment of amps having the least influence on the sound. As someone once said, the preamp is the heart of your system and the amp is your brain. The amp and speaker synergy is just as important as the impedance matching of your amp and preamp. You can have a bad matching amp for your speakers and your system will sound bad no matter how good your preamp is. That's why we call it a "system".
I have to disagree on your comment of amps having the least influence on the sound. As someone once said, the preamp is the heart of your system and the amp is your brain. The amp and speaker synergy is just as important as the impedance matching of your amp and preamp. You can have a bad matching amp for your speakers and your system will sound bad no matter how good your preamp is. That's why we call it a "system".