Hi,
I had quite a lot of set up problems in the beginning. I don't think it is tubes, however the amp does sound even better with better tubes. I would carefully read the operations manual again to make certain you haven't missed anything silly (like I did), and then I would look to cable synergy as the culprit. I was very close to sending mine back, but I am very glad I stuck with it, as it is now the heart and soul of my system. I have never heard the SS amps you own, and it is true the ZH may never equal them in bass slam, but it certainly should not sound as if the mids are overwhelming the bass. In fact it is a bass demon in my experience.
gb
I had quite a lot of set up problems in the beginning. I don't think it is tubes, however the amp does sound even better with better tubes. I would carefully read the operations manual again to make certain you haven't missed anything silly (like I did), and then I would look to cable synergy as the culprit. I was very close to sending mine back, but I am very glad I stuck with it, as it is now the heart and soul of my system. I have never heard the SS amps you own, and it is true the ZH may never equal them in bass slam, but it certainly should not sound as if the mids are overwhelming the bass. In fact it is a bass demon in my experience.
gb