Originally Posted by Aerophone
Would swapping the active filter caps for lower tolerance ones like styroflex 2,5%, o some 1% ones, improve imaging? Since were reducing difference in a pair of speakers response i think it could make any sense.
IMO never a bad idea to set your meter to uF and compare caps on any stereo device(s) where a signal is concerned.
I'm no EE, but it's just occurred to me in practice that when dealing with caps and resistors, we buy these things 10 or more at a time, so it's nothing to sit down and meter each one and set them aside into matched pairs when working with stereo gear like this. find two that are the closest and call it a pair.
again i'm no engineer or tech, but 1% Rs and caps can be incredibly tight if you take the time to match them. For instance I got >1000 Chinese 1% metal film Rs, various values, and it blew me away how close some of these are in tolerance, some showing identical(!) on my Fluke 77mkIV. So you might as well match them up.
</talking out of my arse>