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
Mmccoy, if I'm reading you correctly, it sounds as though you believe your system was re-creating the soundstage at one time, but that it's ability to do so has degraded. In my experience, a change like this is the result of changes in room acoustics, an aging phono cartridge (but you say you're using CD as your source), or, more rarely, aging tubes that have become very mismatched in a circuit. Would you say that anything has changed with your equipment or with your listening room (changing furniture can have an impact)?

More generally, I find that the starting point for excellent re-creation of soundstage (both lateral reproduction and layering in depth) are one's speakers, followed by the source equipment (whether analog or digital). Room acoustics are always a factor, but I've found that one can get good lateral placement in most rooms -- its the accurate recreation of depth that is most tricky to obtain consistently.
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.