Very basic subwoofer question

Yep you just need a good powered sub. I use a Klipsch sw308 with my ls50s in a 12x12 room and it does just what you describe. Room size matters. Personally I would not recommend ls50s for larger rooms. They are just too small even if augmented by a sub and have to work too hard. But in a small to modest size room within their limits they are very good. Also you need a beefy high current amp for ls50s in any case otherwise you can lose a lot.

id say start with one especially if you mostly listen in a particular sweet spot. It can be adjusted for that.  Multiple subs would be for smoothing out bass response across the room if that is a concern. 

Also Ray Brown - Soular Energy is super well recorded and has some great scaling work on it that will reveal if you have subs crossed over too high and output mismatched w mains.

Try the low frequency localization test at audio check.net

and you can get bass localized IF there is a lot of harmonic content in the note / instrument and in case of Orchestra with big arrays with large distances between microphone ( thing DG in the multi mic hey day ), hence mono summing below say 80 HZ.

Bass is/can be directional. Someone here mentioned, it’s the fundamental AND the overtones that give bass directionality

Clearing up confusion- low bass is not directional. Lab tests prove that when the frequency is low enough the sound cannot even be heard at all, at less than half a wavelength.

Sorry, but a little physics is necessary to prove just how airtight a fact this is.

Sound travels roughly 1 ft per millisecond. Not exactly but more than close enough for this. The wavelength of a low bass note like 20 Hz is over 56 feet. Half of this is 28 feet. What this means is the wave has traveled 28 feet before you even know its there. So how in the world are you gonna know where it came from?

Low bass therefore is not directional. Its a physical and psychoacoustic impossibility.

The same physics holds true in the recording venue. This could be why all low bass is mono. I don’t know. Not saying this is the reason. Just saying it could be. Even the most perfect audiophile recording with minimal microphones the only way the bass is going to be significantly stereo is if they are placed very far apart. Even then, even if placed say 56 feet apart, that is at most one wave. The human ear is going to discern this? I don’t think so. The ear responds to volume at low frequencies.

Anyway, back to bass seeming to be directional. Because in my system for sure, and according to Tim and Duke and everyone else with a DBA this is true for them as well, the bass we are getting absolutely definitely does seem to be highly localized and directional at times. Not always. Depends entirely on the material.

So what we have is a situation where the subs can go anywhere without regard to imaging, and yet we will get great imaging. Low bass can be mono, and yet will sound stereo. All because of the peculiar way physics and psychoacoustics combine at low bass frequencies.

I’ve owned a couple of used RELs for years and they work beautifully...I’m not interested in more because standing waves in my tall sloped ceiling listening room are tamed by the sub’s locations, and my incredible listening and tweaking skills developed by years of astute pot smoking.

Yes, it's possible.  I have 4 systems.  All but my main system consist of small monitors and one sub.  In all of these systems the bass is complementary in the way that you describe, subtle, but adding depth and realism to the music.  In my main system I have Harbeth Super HL5 Plus speakers and 4 large subwoofers.  That system will make your liver quiver on certain recordings.

Lesh plays a Modulus Q6 and the open low B string chimes at 31Hz. That same 31Hz B from a concert grand piano has a more content. Phil also uses an OctiBass pedal which adds another dimension to those first position B string stops that add a sense of more air movement.

If this is what you heard live from the front of house system it is absolutly attainable if its on the recording. My wife’s a Dead Head and I hear it clear as day practically every day. I hear it from a 10" sub in the studio or the two 12" in the main system.

I like hearing the differences even when the Fi isn't so Hi...
https://uptonbass.com/instruments/the-upton-bass-double-basses/the-bostonian/

In my bedroom system I don't have a lot of room and some recordings have bass that my tiny speakers simply don't even hint at.

So I added a sub (Golden Ear Subx). I really had to fiddle with placement so I could hear the bass from my bed. A standing wave prevented it going in the spot I felt was the most convenient. That's the thing about one or two subs- you have to fiddle to get it right. I kept the sub output below 70Hz so it would not attract attention to itself, and then just worked with the level so I really was getting the bass notes. The main speakers roll off at about 60Hz (KLH model Nineteens) so this worked out pretty well.


A Distributed Bass Array would have worked better (I could have heard the bass throughout the room rather than just near the bed) but since the goal was listening from my bed that was not important.

Thanks, all, for your thoughtful responses -- they are much appreciated.
-- Howard

You can improve the bass with subs -- improve the sound overall with subs. What you do depends on your aspirations for the system.

In my desktop system, which has Harbeth P3ESR speakers (5" woofers), I added a used B&W ASW610, a 10" powered sub, and it improved the presentation a lot, in just the way you asked about.

As others have said, multiple subs are helpful in smoothing bass nodes and increasing the sense of ambiance. You might start with one, and if you like the result but want even more, get a second matching one to try. If you have room, 4 or more subs can smooth the bass even more.

Have fun!

For 2-ch audio, a pair of subs is very much capable of achieving high quality bass....I was able to do so with a pair of REL’s. 

The bass you get with multiple subs in a DBA is beautiful at revealing all the many differences between recordings. The concept itself is odd mostly because such an approach would never work with higher frequencies. Putting more speakers around the room would only muddle midrange and treble. There would be more volume, but less precision. With bass however there is more volume AND more precision! The character or quality of bass you can get with a DBA is simply impossible to achieve with any one sub. Find one, if you can, or build your own. You will see.

Sorry for having been unclear. I mentioned the recordings I did simply as examples, not to imply that all is generally fine -- except on those records. My bad.

Honestly, since you are talking about this being recording specific, it sounds like what you need are tone controls. Read more about getting the right bass for you here:

https://speakermakersjourney.blogspot.com/2020/04/how-to-not-buy-subwoofer.html

Bass is/can be directional. Someone here mentioned, it’s the fundamental AND the overtones that give bass directionality

For music, I am a fan of a pair of mains, no ports, and a pair of self-powered subs, located with the mains for stereo bass.

For video, a single self powered sub can be enough.

Thanks for this. I look forward to checking it all out.
-- Howard

Four subs, of virtually any size, brand, model and power, will give you just the sort of seamless foundation you desire. Its really as easy as buying four, putting them different locations around the room, and adjusting the levels. Do it right and you will never even know they are there, until you notice all kinds of bass that was only hinted at before is suddenly clean and clear and full of character. You will also notice your midrange and treble are clearer, and the sound stage is more enveloping. You feel it is no longer just in front, you are in it.

Its called a Distributed Bass Array. It can be any combination of subs. Do a search. Study the system https://systems.audiogon.com/systems/8367 Read the reviews. Its totally the way to go.