Do you have the original Quests or the Quest-Z? I had (still in basement) the original and they are a tough impedance curve, and may need quite a lot of oomph from the amp. I tried the Mark Levinson ml-27, which sounded wretched. I tried a Classe' CA-200 that dimmed the lights in the house on peaks. I tried the Pass Aleph-0's, which were just boring. The two amps that did well was the McCormack DNA-1 and the Classe' CA-300, and I ended up with the CA-300.