I have a pretty basic question about a sub-woofer's effect on stereo imaging that will reveal my ignorance if nothing else (I'm far from an expert on many of the audio concepts discussed here). I'll start out by saying that I've never used a sub-woofer in any of my main stereo systems. The only sub-woofer I've ever owned is the one that came with the CHEAP computer speakers that I used to have connected to my old PC back in the 90's. Sadly, those were Altec Lansing computer speakers that I was very excited to purchase until I actually heard them ( I had no clue at the time that they weren't REAL Altecs--all I knew about Altecs back then was that the Valencias my brother owned and the Model 9's and VOTT's (A7's) that I owned sounded GREAT). But I digress....
Anyways, the speakers that I'm currently using for my main stereo system at home are Model 19's. They sound amazing and get great/deep/clean/powerful bass the way I have them E.Q.'d and positioned in my room--when you crank them up you can FEEL the bass in your chest--it really is DEEP and powerful. So, I have no need to buy a sub-woofer--this is more an "inquiring minds want to know" type question and I can think of no better place to ask it than here. The question occurred to me when reading the thread Old Guy posted recently regarding the Altec Lansing coffee table sub-woofer (man that thing looks cool!). Hopefully any info gleaned from this thread will be of interest/value to others here as well.
Basically, when I'm listening to a "good" music recording on vinyl (or CD or DVD) on my Model 19's, it is often apparent that a lot of effort went into the production (by an engineer(s), producer(s), artist(s), etc.) to not only get the mix/E.Q. just "right", but to also get the stereo imaging just the way they want it. For example, I might hear a cymbal panned nearly all the way to the right, a guitar part way to the left, a kick drum dead center, a bass guitar part way to the right, etc. Or, if I'm watching/listening to a movie on DVD there might be an explosion in a certain scene and you can here the thunderous bass panned to the left (for example right where McGruber's pickup truck explodes!). With the Model 19's that I currently use as my "reference" speakers, the soundstage on a great recording is phenomenal. The stereo imaging even in the lowest of frequencies is crystal clear--you can hear precisely where all the instruments/sounds/sound effects/etc. are panned. Pretty obvious to most of you by now as to what my question is going to be. Here it is anyways:
If you have a stereo recording, and just one sub-woofer, isn't that going to skew/throw off your stereo balance/soundstage in the lowest frequencies? It seems to me that if your speakers are lacking in extreme low end, the concept of adding a sub-woofer to compensate is a good idea--a quality sub-woofer can fill in the low end nicely. But won't it be a TRADE OFF at best? Yes, you'll finally have the extreme low end that your speakers lacked, but won't you be giving up the precise stereo imaging (in the low end at least) that a producer/engineer/etc. worked so hard on to get just "right". Or, worse (?) yet, will the frequencies that the sub-woofer produces be so low that it's hard to pinpoint exactly where they're coming from (thus, completely "blurring" your stereo imaging/soundstage in the lowest frequencies)? If I'm listening to an album and the bass guitar has always been panned partway to the left on a particular song and I have the sub-woofer in the center of my room--won't that pan be affected? Will McGruber's pick-up truck not sound like it's exploding from the precise spot in the soundstage that it used to explode when watching the DVD? I'm guessing I'm not the only one here who wouldn't want their soundstage/stereo imaging to be skewed/blurred even if it's "just" in the lowest of frequencies.....