The Onyx is a whole different amp than the Topaz. Different output tubes, different design, different price. I have heard some negative comments about the Onyx. I didn't here that they were honky, but did hear that they were thin in the midrange and somewhat sterile sounding. Anyway, I'm not here to flame anybody about their opinions. I appreciate all comments of experiences with different equipment as long as they were done ernestly. And I've never known you to post otherwise. It's only through varied opinions that one can fairly judge what might be best for them. You may want to say what your system was at the time. That way we can all know what to avoid when system matching.