Quote: Originally Posted by upstateguy /img/forum/go_quote.gif What I took away from the experience was that I heard what I heard over a two week period, only to find out that in direct comparison the differences I heard did not exist and then to have my initial impressions return when the comparison was over. The "why" is what I would like to explore. I didn't really get to this part of your question in my previous post. This is part 2, I guess. I really don't know how to help you make sense out of your experience. Again, what you heard, or thought you heard, at different times could be based on so many variables, it is hard to form any intelligent conclusion about them Furthermore, it's not clear to me what you mean when you say you did a "direct comparison" of the differences, and what you mean when you said you heard differences again "when the comparison was over." Does that mean one of the DAC's was gone, and you were remembering what the other DAC sounded like, or something else? Also, I would need a lot of other information. Just as an example, did you listen to the same music at all times in all of the listening sessions, or different music at different times. I find the HD-650 to sound pretty close to the K-701 on certain music, and very different on other music. That could cause some problems in trying to draw conclusions if I were comparing them over a limited time, sometimes together and sometimes separately. Also, when you did the "direct comparison," how was that done?