Originally Posted by askme_scor
I read somewhere that 6006 model is brighter than 6005. Is it true?
No, not true. Much much more likely there was a very slight volume difference, hardly noticeable as such, if at all, but very significant in terms of being able to generate a mis-perception of there being a sound quality or tonal difference between the two. Either that, or there was some setting difference between the two that would account for the difference heard.
Plus, even though some people really get offended when this is suggested, the human auditory system is quite susceptible to detecting differences even when none exist. We're wired that way, so to speak, so it can be tricky to know if a difference is actually there or not. This is where measurements and a cursory knowledge of the history of bias-controlled listening tests come in. Both can provide some context as to when we can rightly expect there to be legitimate sound quality differences or not. And in the comparison of AVRs, sound quality differences aren't very likely at their core level, i.e., before EQ features are put into play.
Anyway, the topic of sound quality difference between receivers has been hashed out many times here in this forum and you will never find 100% agreement. It's at least something to be aware of, if you've never encountered these ideas before.
Or in ccotenj's tl;dr "cutting to the chase" version of my post, the answer is, "no".
Bottom line: if the choice has come down to those two models, pick solely based upon the better deal and if one has an extra feature or few that you want or need that the other model does not.