Colin, if the acoustical conditions are significantly different upstairs, the sound with the M22s will also be significantly different, but it'll have nothing to do with NAD vs Pioneer amplification, both of which are uncolored. As it stands now it's the M22s alone which strike you as "extremely bright". My experience with them for the past eight years shows nothing of the sort except on poorly-recorded material which exhibits that characteristic on an accurate speaker. However, if this continues to be your experience, then the program material which you prefer is best played on some other speaker.
