does a subwoofer kill stereo sound?


I was wondering whether adding a subwoofer to a pure stereo system would cause any harm to the soundstage and other features of the system. What are your experiences? Should one buy a subwoofer to complement a great bookshelf pair (that may be lacking some bass) or necessarily one would have to buy a new par of speakers with deeper bass?
tvfreak
Magfan, You made this comment: "If I had the $$, time and inclination, I'd work on NOT running my panels full range. I suspect there are additional benefits in that direction, but also a whole new learning curve."

For my tastes, I found taking some of the lowest-frequency bass load off the main panels made at least as big an improvement as adding more and lower-frequency bass did. Articulation of subtle nuances (and some not so subtle) improved dramatically. My main complaint with add-on subwoofers is most just add bass and do not give the main speakers some relief where they need it the most. And you are right--it is a new ball game.
I can never get why people buy very expensive top shelf amps and then let the bass be done by amps built into the subwoofer cabinet. Is that really the best way to do things? Or do most people have a really good amp to run the subs too? How about using a seperate amp and preamp to run a subwoofer system?

As a side note, I have caught a dealer demoing SET amps but had a powered subwoofer playing hidden behind some other speakers. I am getting very good at detecting bass that should not really be there. I can tell if a subwoofer is in the system and it usually annoys me too much. imo, a sub is not really needed if you have great full range speakers AND the room to support low HZ. but they may be fun to play with and that is okay at time too.
6550c,

My understanding is that high quality amplification is less important for bass than for other areas of the audio frequency band. But yes, there are certainly passive subs that let you choose the amp to use with the subs. I use a pair of passive NHT subs with 2 bridged Emotiva BDP-1s. The main advantage of this for me is the ease of dialing down the level of the bass easily for late-night listening. Most of the subwoofer attenuators are around the back. and awkward to reach for...

6550c

Your comment spoke to me . People that want more bass are really just not getting enough satisfaction from their system. They seem not to know why, so of course they seem to blame the lack of bass.

Bad move...... If the system was satisfying the bass would be the least of the problems.

You are right on.
woith some speakers only going down to ,,say 50 hz, your missing alot so maybe a sub is right in some systems.