Improving imaging


I'm interested in hearing from the experts the following:

What component, in your opinion, contributes the most to creating a 'discrete' soundstage...

i.e. the 'most important' component/element, etc. that contributes the most to overall imaging. For the purpose of my question I define 'imaging' by being able to ascertain where instruments are located from left to right, front to rear across the overall soundstage. Assume a well mixed/recorded CD 'source' (ala Telarc, etc.).

The reason I ask is I'm not sure if it's my aging ears or my equipment but over time it seems everything is now pretty much 'placed' either primarily on the left or right channel, or 'summed' in the middle. Displacement outside these 3 main locations seems to now be almost to subtle to distinguish from 'left/center/right'. And thus for sure, hearing the tymphanies 'behind' the strings (or the drummer behind the guitar behind the sax) is pretty much non-existant.

I'm not trying to get into 'which brand sounds best', or 'tube vs solid state', etc. kind of debate, just trying to determine if it's my ears or my equipment that is obviously declining and if it's likely my (2 chan) system, which piece should I concentrate on first in order to improve imaging.

thankee in advance!
mmccoy
Ditto, Rushton above. I would add, the electronics' driving power: does the power amp adequately drive yr speakers, does the pre adequately amplify the source sound. *If* this is not a recent phenomenon, as Rushton notes.

Good luck!
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I was going to post a similar question since I have noticed some smearing or stretching of sound sources with my system. Mostly it seems to be front to back (if that's possible), but there is some slight lateral smearing which seems to be related to an instrument's frequency. I couldn't do much with room treatments, but according to the posts above, it's probably time to upgrade my entry level speakers. Prety much what I expected, just nice to see it confirmed.
If your system had good stage at one time and now it doesn't, even though you haven't changed audio components or room components, don't overlook the possibilty that one or more of your cables has developed a problem. This problem could range anywhere from speaker wires in which the conductors have oxidized to interconnects that need their connectors cleaned. Get thee to www.caig.com immediately. As a former Cramolin user, which I believe Caig manufactured, I have now become a staunch believer in Caig'sProGold and DeoxIt. In fact, only last night I used them to breathe new life into my system by cleaning the ends on my silver digital cables. This stuff works, and even Boeing and NASA know it.
Excellent point, Dougholdco. A cheap, quick check would be to at least pull-out and push-back-on your interconnects at all connecting points, Mmccoy. That will clean the connections enough to get a sense of whether this is a contributing factor in your situation.