Small or large sub for music

Large subs go deeper, better and louder.

HOWEVER! Larger subs are harder to match to the room. The lower they go, the more room modes you are likely to find. 

With proper room treatment, and good EQ, a good 15" sub will do music or movies absolutely superbly with any speaker. 

Without those two .... a small sub is far less dangerous and more likely to work for you.

Erik,

I use the HGS-10s and 15s with SMS-1 bass managers that provide acoustic room correction.  I noticed when I played the Saint-Saens 3rd symphony that the pedal notes are not as well realized by the HGS-10s as they are by the KEF Reference 107/2s.  I think the 10s extend to just below 30 Hz whereas the 107/2s and 15s extend to below 20 Hz, so pedal notes have that more felt than heard vibration I sense at live recitals.

db

Just get a larger room, sorry thats not an answer...big woofer more full deep bass, small woofer better tunefulness most the time, big woofers are better for some , small better for others, depends on what sub what room, what you like... thanks
Matt

Room modes cease below the frequency where the bass wave is twice the length of the longest room dimension. For 18 feet this is 31hz. Smaller rooms, it is higher.

Subwoofer size has nothing to do with how boomy, fast, or slow it sounds. That is a function of qtc and group delay.

The largest effect on how a sub sounds is placement and the room. Room treatments help with ringing, dsp with frequency response at the listening position.

I ran velodyne subs for 25 years. F1000, ULD-12s in stereo, HGS-10, HGS-12. I have moved on to Rythmik. A L12 in my office and F15hp in my main system. The L12 is the equivilant of an HGS, the F series takes the HGS and wipes the floor. It is like a layer of crud cleaned off, nearly dry sounding, articulate, deep, and much higher output capability. It is a great step forward and well worth the upgrade. A pair is recommended to minimize room modes, the f12 probably being more than sufficient.

Two quibbles:

1 - Room modes ARE ringing
2 - Once bass traps are in place, DSP helps with ringing and nulls. .

Not going to argue this, plenty of professional acoustics literature out there. The bass traps help de-energize the rninging, and make DSP’s possible. You can even clean up nulls this way.

The combination of sub placement, room acoustics and DSP all contribute. Well done, they are lightning fast and completely organic sounding, and bigger = better.

However, poorly done, limited placement, no bass traps, no EQ, a small sub may often sound better.

Best,

Erik

I also have a pair of LS 50s that I have set up in a small unused bedroom. I'm using a JL Audio Dominion 108D sub that is down -1.5dB at 31 Hz. I added a second identical sub but found that it overpowered my small listening room and ended up returning it. I'm very pleased with the balance and speed of this single smaller sub.

I have a Zu Audio Undertone sub
it is a sealed sub, large, about 70 lbs, runs cool due to Class D, goes down to 14hz. They use the Hypex switching modules and a large 12 inch cone from Eminence (Kentucky). 

I run it with a pair of Zu bookshelves or with Dynaudio floorstanders. 
The main reason I like it is bc it is so effortless and powerful, so that the LFE integration is totally seemless. 

Hello dbphd,

Your username is familiar to me from other threads so please disregard if I’ve given this advice to you previously.

I’ve learned through research and personal experience that great bass response for both ht and music can be attained in any room by using a distributed bass array system of 4 subs that are placed not haphazardly or conveniently but positioned in a more strategic and progressive process which I can elaborate on if you’re interested.
I utilize a complete all in one DBA system called the Audio Kinesis Debra system that I bought a few years ago for about #3,000. I think both the AK Swarm and Debra systems are still at about $3K with a choice of finishes. However, any 4 subs can be used to create a distributed bass array system with similar results. The only caveat being a need for the room space to accommodate either your 4, or the somewhat smaller Audio kinesis, subs in your room.
The key is having 4 subs which almost magically reduces room bass standing waves that results in less room bass nodes in virtually any room if they are located properly. It’s actually based on scientific research done by several PHD acoustical engineers, Dr. Floyd Geddes and Dr. Floyd O’toole and others,
I started a couple of threads on these bass systems. Here’s the latest one that you may want to read for further info:
https://forum.audiogon.com/discussions/anyone-else-using-an-audio-kinesis-swarm-or-debra-distributed...
The beauty of deploying a DBA system is you obtain excellent bass response throughout the entire room without the need for any room treatments, equalization or room correction hardware or software.
The Audio Kinesis Swarm system(almost identical to the Debra system) was also reviewed by The Absolute Sound a few years ago. Here’s a link to that review:

www.theabsolutesound.com/articles/audiokinesis-swarm-subwoofer-system/

I can verify that their review is completely accurate to the results I’ve achieved in my system and room.
I have absolutely no connections with Audio Kinesis. I’m just a very satisfied customer
Tim

There is much more to consider than just the size of the cone. The magnet structure, the amps power, the equalizer in the sub, and then the room, placement, etc...
Rel subs are some of the best out there and they have smaller cones compared to others, Plus, Rel recommends hooking up the subs so the main speakers run full range and the Rels just add to the lower octaves to the mains.
Personally I prefer multiple smaller cones in a sub instead of just 1 larger cone, same goes for my main speakers. Instead of getting a 15” woofer, I would get multiple 8 or 10” woofers.

" Two quibbles:

1 - Room modes ARE ringing
2 - Once bass traps are in place, DSP helps with ringing and nulls. .

Not going to argue this, plenty of professional acoustics literature out there. The bass traps help de-energize the rninging, and make DSP’s possible. You can even clean up nulls this way.

The combination of sub placement, room acoustics and DSP all contribute. Well done, they are lightning fast and completely organic sounding, and bigger = better.

However, poorly done, limited placement, no bass traps, no EQ, a small sub may often sound better.

Best,

Erik"

I think we fundamentally agree, but are not quibbling past each other.  As I understand it:

1)  Treating room modes by room treatments reduces decay time (ringing).  

2)  To optimize bass in a room takes a combination of setup, room treatment, and DSP.  Just like a three legged stool, all must be applied properly to get a good outcome.  

I thave tried a ML 12 in my 17x22 room, and it was to loud for stereo music, and I found  the stereo image and depth were diminished.  So, I did not go for a sub, but try it, and I am now fixe with it.  But I would suggest to try 2 smaller sub, if you listen in stereo music.  May be it woill work with your room.  So for me, one big sub kill the magic of music.

I'm not sure whether it's a more appropriate question than your original, but it's certainly a significant factor when weigh sub-woofers for music and that is whether you purchase ported or non-ported speakers. I prefer non-ported subs as they're less boomy, faster and more natural sounding. But hey, that's just one man's opinion.

I'm firmly in the "DSP robs the music of some soul" camp (I don't trust the sonic opinions of the designers...how do they know what I want to hear?), and think a normal room (meaning with furniture, rugs, and stuff other than traps and damping panels) can sound great. If you live in a steel shipping container with no furniture you have other issues to worry about that DSP ain't gonna fix. Using 2 subs takes care of a lot of the aforementioned room mode issues if they're receiving the same signal (not stereo) at the same time...it just works. Also, if sub levels are too loud, turn it down. 

Thanks for all the advice.  Whether I use 10, 12, or 15 inch subs I will use a pair, most likely placed just behind the speaker stand.  Looks good and sounds good in my experience.  The sub will be non-ported.  

I've almost decided on rosewood KEF Reference 1s.  A pair Rhythmic F12s in piano black might be a good upgrade from my aging Velodyne HGS-10s or 15s.  I might continue to use the Velodyne SMS-1 bass manager that provides acoustic room correction, although that may be redundant with the F12s.

Thanks again for helping me firm up my plan.

db

I have two Rhythmic 15 inchers. I too thought I would place them on the inside of the tower speakers. That didn't work, so I went to the printed manual and they suggested placing them on opposite ends of the room pointing towards the middle. Magic! The difference was night and day.

dbphd,
Acoustical engineers have proven that bass response performance in any given room improves as the number of subs is increased and that the size of the drivers in the subs is much less important than the actual number of subs in the room. 2 will perform better than 1, 3 better than 2 and 4 or more is just exceptionally good.
Of course, these experts realize that there’s a limit to the number of subs consumers will allow in their home rooms; or at least that consumers’ significant others will allow in their home rooms.
Through research, they discovered statistically that using 4 subs in a room provided the vast majority of bass performance benefits of using many more subs did while still remaining a feasible number for home use if reasonably sized.
In your situation, I’m almost certain that using 4 moderately sized subs would provide significantly better bass response than 2 subs randomly placed with one behind each main speaker. I believe this will hold true irregardless of the price, quality or driver size of the subs you choose based on specific scientific research on this very subject and my personal experience supports this conclusion.

If you have a decent sized room and want state of the art bass response, I suggest you at least read the Absolute Sound review of a DBA (link below) so you can make a more informed final decision.

https://forum.audiogon.com/discussions/anyone-else-using-an-audio-kinesis-swarm-or-debra-distributed...

Best wishes,
Tim

dbphd,

Sorry, I linked the wrong link for The Absolute Sound DBA review.

Here’s the correct link:
www.theabsolutesound.com/articles/audiokinesis-swarm-subwoofer-system/

I also forgot to mention that the Audio Kinesis subs are positioned facing and within an inch of the wall. So all you see of them in the room is the attractive wood you choose covering the top, back and sides of each sub (connections are on the bottom).   I use the supplied spikes for each on my carpeted floor. My wife says they look like art gallery pedestals and usually has a vase of fresh flowers atop 1 or more.

Tim

Have you tried daisy chaining all four?

" Have you tried daisy chaining all four?"


m-db,

No, didn't think there was a need.  The Debra system's 1,000 watt amp has 'A" and 'B'  sub/speaker output sections, each with its own 'Left' and "Right' sub/speaker outputs, so  4 sub/speaker outputs total.  I run separate custom speaker cables to each sub  that are routed through the crawl space underneath my room.  

Tim

Sorry for being so brief. I meant to say daisy chaining the four powered HGS subs via the Dayton's EQd line level (RCA) connection using each subs 1000 / 1250w amplifiers. 

I'm not sure of the ohm rating of the two HGS drivers. I'm assuming if they're anything below 8 ohms you may have presented the Dayton amplifier with a less than its combined 4 ohm minimum load which could affect the subs performance and possibly damage the drivers.

Blue Jeans or MonoPrice cable offer reasonably priced custom lengths of RCA cable.  

m-db,

     Okay, I understand now you weren't directing the daisy chaining question to me.

Woops,
Tim

I use a pair of JL Audio F113V2 subwoofers, each with 13.5" drivers and 3000 watt amps built in, each also weighing in at 133#.

To Erik_Squires excellent point, my "man cave" had an extremely obnoxious "one note" it would add, no matter what the bass players were playing, and it was very loud.  So, I had to purchase a calibrated microphone and "REW" (Room EQ Wizard) software and eventually apply 10 bass traps to the room, to get the low bass under control.  Now it sounds great, but it was not easy getting there!

One thing about my comparison of the JL models, the F112V2 subs (12" driver, 1800 watt amps) were probably a better match for stand mounts, as they go higher in the bass range before they roll off.  In my case, my F113V2's pair with some Focal Sopra No2 floor standing, three way speakers.

More important, IMO, is to have a SEALED sub for music.

"More important, IMO, is to have a SEALED sub for music."

Can anyone provide a supportable reason for this, or is this just an ad nauseum repeating of inaccurate information? 

Subwoofer sound is primarly dictated by QTC and group delay.  It is easier to build a sealed subwoofer with a low QTC and group delay (just throw a driver in a large sealed enclosure, the bigger the lower the QTC), but a vented subwoofer (whether ported, slot load, transmission line, or passive radiator) works just as well or better when properly designed.  With decent quality subwoofers, the vast majority of issues people have are room and tuning related, not equipment related.    

Just a few music focused manufactures using vented designs:

Vandersteen- Yep, slot load, including his $18,900 Sub Nine.  Perhaps someone should let Richard know he isn't building his speakers correctly. After all, he is just a truck driver from Hanford, what does he know?   

Wilson Audio-  Yep, ported.  But hey, David Wilson was just just selling speakers to deaf people.

Legacy- Passive radiators.  I only heard Legacys once and was less than impressed, but it was 20 years ago and the room was less than optimal, so I really can't say they are good or bad.  That said, they seem to be among the most liked brands.  But again, perhaps Bill Dudleston doesnt' know what he is doing.  Someone should let him know he should change his designs, as they are not audiophile approved as sealed. 

   

Love my JL Audio F113 great sub 

Hello ejr1953,

      Let me get this straight, you bought and installed 2 JL Audio F113V2 Fathom subs, JL's latest and finest that are huge, weigh 133 pounds each and have a msrp of $4,500 each, but were initially greeted with "one note" bass?
      I feel for you, brother, that must have felt like a punch in the gut.       
     Your dealer then added insult to injury and sold you a calibration mic, room correction software and 10 big and expensive bass traps to fix the problem? 
     You must have the patience of a saint, I'm getting worked up just hearing about it. 
      I'm sorry, ejr, I know you're pleased now but  the Fathoms still seem like an unnecessary compromise in many aspects from my perspective.  
     Is it too late to just return everything and start from scratch?  I can tell you, with a high degree of confidence, that either an Audio Kinesis Swarm or Debra bass system would be a significant upgrade from the Fathoms in all respects at a price about $1,500 less than a single Fathom.along with a free 30-day in home trial period.
  
    However, I get the sense that a quality bass system is a much higher priority for you than price.  I'm as certain as I can be that either a Swarm or Debra bass system will provide state of the art bass in your room while also eliminating the need for any bass traps, mics or room correction software.  I know it will provide the absolute opposite of "one note" bass, the ability to choose your cutoff frequency between 30-200 Hz on the front of the 1,000 watt supplied amp and  a choice of wood finishes that actually allows the subs to appear to my wife and I like the art pedestals you often see in the better art galleries.

Tim     

@mcreyn I will let RV know !!!!! I knew there was something wrong with my Model 7, so I tried an experiment, IF you slide the M7 amp over you can block one of the slots, IT improves the base by 50%
.....

mcreyn:

" but a vented subwoofer (whether ported, slot load, transmission line, or passive radiator) works just as well or better when properly designed. With decent quality subwoofers, the vast majority of issues people have are room and tuning related, not equipment related."

     Well said!  I couldn't agree more.

     The Swarm and Debra subs are 'vented enclosure for correct roll-off to compensate for room gain (ports can be plugged with supplied plugs, if desired)'.  I've tried my Debra subs both ways and preferred them unplugged.

Tim
     

noble100
Yeah, my daisy chain remark was directed to the original poster dbphd but I failed to make that point in both of my posts. 
I then confused your use of the Dayton Sub amplifier and High level conectivity with dbphd's HGS subs.

In the word of Rosan Rosanna Danna, "Never mind"! 

ejr1953
When I did a half baked subwoofer comparison between my Velodyne DD-18 with two other sub owners of a REL Studio III and a JL Audio Fathom F113 (v1) using the JL Audio ARO there was a slight but audible peak just below the main speakers crossover point.

This was clearly visible using the Velodyne Room Optimization program. I was able to dial some of it out using the F113s LP freq. (Hz) dial. Bypassing ARO and using the Velodyne Manual Optimization I was not only able to clean up the crossover point make some Q adjustments and cut and boost a few other places to really smooth out its response and improve the F113s overall performance.

I understand JL Audio has made improvements with their v2 and is also marketing an ancillary companion crossover component. Regardless, the JL Audio is a very fine system that provided nearly the same girth of output of the DD-18 that seriously belies its 13" drivers size.    

   The Swarm and Debra subs are 'vented enclosure for correct roll-off to compensate for room gain (ports can be plugged with supplied plugs, if desired)'. I've tried my Debra subs both ways and preferred them unplugged.

The Swarm and Debra subs are an excellent example of using science and good acoustic theory to maximize the benefit for the minimum dollar.  They have addressed the biggest issue, the room.  It can be done with any 4 subs.  You should see what some of the crazy home theater guys do, as the Swarm would never have enough deep bass for them (they want 120db @10 hz), things like quad JTR Captivators.  Not to plug another forum, but AVSforums in the subwoofer section has some really great information on setup, tuning, and objective reviewing.  The home theater guys have done more for good bass than just about anyone.  

"More important, IMO, is to have a SEALED sub for music."

Can anyone provide a supportable reason for this, or is this just an ad nauseum repeating of inaccurate information?  

It's a myth, with a completely different issue coming on. Sealed have higher f3, and fewer problems with the room. If you know what you are doing you can make a ported sub work fantastically. If you don't, get a sealed 10" sub and leave it alone. :) 

"More important, IMO, is to have a SEALED sub for music."

Can anyone provide a supportable reason for this, or is this just an ad nauseum repeating of inaccurate information?

Yes, it’s a myth. I’ve got two of these ported Talon Roc 2002 monsters for my 2/ch rig in my small/moderate size room. 140 lbs each. After years of owning just one, I was astounded to discover how much I was missing when I added the 2nd. Now, I easily hear rhythm, timbre and texture - way down deep. It’s especially great at low volume listening. No boominess. No one-note thumping. No DSP. It did take a while to integrate them seamlessly.

Subwoofers are a bad solution for inadequate speakers. They are mutually exclusive with high fidelity because they can never perfectly integrate. Some people and rappers don’t care about sound quality. Low-Fi is fine for them. For the rest of us, subwoofers only belong in the home theatre. 

They are mutually exclusive with high fidelity because they can never perfectly integrate.

<< cough >> bs << cough >>

Just because you have never known how doesn’t mean it is not possible. However, it takes high degrees of skill and experience. It is quite closely related to speaker crossover design. This is why I often believe that avoiding the sub is a better option for many. That’s not the same thing as saying it cannot be done. It is glorious when done right, but few live to hear it.

Best,

E

Subwoofers are a bad solution for inadequate speakers. They are mutually exclusive with high fidelity because they can never perfectly integrate. Some people and rappers don’t care about sound quality. Low-Fi is fine for them. For the rest of us, subwoofers only belong in the home theatre.

Another clueless statement! Zero understanding of the importance of room interaction.

Many contemporary full-range speakers (very high-end) now have amps built-in to the cabinets - with EQ capabilities - to expressly drive the woofers. This design allows better implementation/integration with room issues.

Using separate subs with stand-mounted monitors or two-way floor standers have the advantage of moving the subs to the optimum location in the room - allowing the system to be full range.

sleepwalker6519 posts08-21-2018 8:22pmSubwoofers are a bad solution for inadequate speakers. They are mutually exclusive with high fidelity because they can never perfectly integrate. Some people and rappers don’t care about sound quality. Low-Fi is fine for them. For the rest of us, subwoofers only belong in the home theatre.

You know I always thought that Wilson, Magico, and Vandersteen were Low-Fi with their subwoofers blasting along with their statement products at audio shows.

Thanks for clearing that up.  

" The Swarm and Debra subs are an excellent example of using science and good acoustic theory to maximize the benefit for the minimum dollar. They have addressed the biggest issue, the room. It can be done with any 4 subs. You should see what some of the crazy home theater guys do, as the Swarm would never have enough deep bass for them (they want 120db @10 hz), things like quad JTR Captivators. Not to plug another forum, but AVSforums in the subwoofer section has some really great information on setup, tuning, and objective reviewing. The home theater guys have done more for good bass than just about anyone."

mcreyn,

Wowie Wow Wow McWoofer.....Testify!
You stated: " The Swarm and Debra subs are an excellent example of using science and good acoustic theory to maximize the benefit for the minimum dollar. They have addressed the biggest issue, the room. It can be done with any 4 subs."
What happened? Did you actually get a personal audition of a distributed bass array (DBA)? In any case, your quote above is an excellent summary of what the Swarm and Debra represent. And, yes, the DBA concept’s ability to transform a room’s bass response using almost any 4 subs is like magic but true, science really is like magic but real.

"You should see what some of the crazy home theater guys do, as the Swarm would never have enough deep bass for them (they want 120db @10 hz), things like quad JTR Captivators. "

I am familiar with the ’crazy home theater guys’ typically loitering at AVSforums and other a/v sites with their brute force approach to reproducing bass in a home environment. However, I have too much respect for the supporting mechanisms and other surfaces in my home to adopt this ’Bringing Down the House’ approach.  I can't recall ever desiring more bass listening to any source or content.  Besides, the supplied amp has controls for setting the overall level - I can recall tweaking that and the crossover frequency (currently the level is set at about half and cthe rossover at about 40 Hz)
     Loud and overpowering is not my conception of ideal bass. My version of ideal bass for my combo ht and music system is more nuanced, having the dual qualities of power and definition required for state of the art bass response reproduction of both.

Tim

@noble100 --

(I am familiar with the ’crazy home theater guys’ typically loitering at AVSforums and other a/v sites with their brute force approach to reproducing bass in a home environment. However, I have too much respect for the supporting mechanisms and other surfaces in my home to adopt this ’Bringing Down the House’ approach. I can’t recall ever desiring more bass listening to any source or content. Besides, the supplied amp has controls for setting the overall level - I can recall tweaking that and the crossover frequency (currently the level is set at about half and cthe rossover at about 40 Hz))
Loud and overpowering is not my conception of ideal bass. My version of ideal bass for my combo ht and music system is more nuanced, having the dual qualities of power and definition required for state of the art bass response reproduction of both.

Some of the guys over at the AVS forum have true monster sub setups that would indeed be able to bring down the house/apartment building if called upon to "stretch their legs," and that could fill even large auditorium cinemas with bass impact and depth that would satisfy and impress most. I guess having sub setups like that is not about letting them sit idly at <100dB’s, but to feel them in action - loudly at that, and with a physical sensation that would dwarf any typical hifi sub-system. It would be safe to say many of them like their subs run HOT.

Having said that "loud and overpowering" is not all there is to it. I would agree with the mention that there are extremely experienced individuals over there (at the AVS forum) who have close to exhaustive knowledge of sub implementation, and to whom "overkill" is only an approximation to sufficient headroom; headroom being one of the key words and signifier for the measure of bass quality. It’s about achieving 20dB’s of headroom at the minimum, so to have distortion levels in the lower single digits even at the loudest levels you’d ever desire down to below 20Hz. You would think it’s only about blowing your hair/head off with über-SPL’s, but from the setups in this caliber I’ve heard there’s nuance and definition in abundance, and not least a relaxed, enveloping and totally effortless presentation that’s quite addictive. I definitely subscribe to the duality of "power and definition," and this way you’ll potentially get both in measures hard to describe.

Generally I find audiophiles to be almost intimidated by or ridiculing air displacement prowess and high sensitivity and SPL capabilities. It’s too easy and reductive just labeling it as an in-every-case brute-ness, and at the same time robbing it of the "sophistication" audiophiles are so eager to pursue. Again, there’s more to than that..

Hello phusis,

     Your post was a well written, reasonable and articulate defense of the monster sub setups of some of the AVS forum members. 

     I like to think of myself as reasonable, open minded  and resistant to stereotyping .  Your post made me realize that I've seen and read about many of these systems on AVS and other sites in the past but never listened to one in action.  

     As you constructively pointed out, I believe I was stereotyping these monster sub setups as 'bass by brute force' and dismissing them as not capable of providing both high quality bass power and, simultaneously, high quality bass definition.  You've heard some of these monster setups and claim these are built by knowledgeable bass enthusiasts with the skills to attain both impressive bass power and bass definition.  
     
     So, I think it's best if I just take your word for the capabilities of these monster setups, thank you for pointing out my stereotyping, try to refrain from doing so in the future and try to get a personal audition of one of these monster bass setups soon.
  Thanks,
     Tim  

It's nice to use subwoofers for theatre systems. The best option is to buy speakers for your audio system that do NOT need subs.

"It’s nice to use subwoofers for theatre systems. The best option is to buy speakers for your audio system that do NOT need subs."

Why? The best speaker placement for imaging and bass are generally mutually exclusive!!!!! Are you willing to place 4 main speakers around your room at the optimal positions to minimize standing waves (ala a swarm setup)?  Show me a full range speaker system that can go flat below 20hz that costs less than $10,000 a pair and is optimized for placement in the bass where the imaging is the best. The system in my office (a used set of Totem Mites and a Rythmik L12 for a total cost of $900) does that comfortably (when I say comfortably, it starts to roll off at 23 hz is and 1 db down at 20hz).

Even with "full" range speakers, good subwoofers with proper setup make a great difference. The problem is most people want to plop them down, spend no time setting them up, and then turn them up too loud resulting in a bloated, slow, plodding sound.

It takes time to get a sub properly setup and integrated. In my office, it took over 100 sweeps with REW with the sub in 3 different places to get a really good integration where it disappears. It can take a lot of playing with phasing, crossover and placement to get it right, but once you do, you can enjoy truly full range sound that lets you hear things you never knew existed.

I have a “full” range speakers supported by 2 JL212 subs. The subs Integrated with the main speakers so well that now I cannot listen to the system without the subs. The quality of the subs is very critical. 

When I first purchased my Wilson Max II’s and was talking about adding a new sub, someone on this forum laughed asking why I would even want a sub, using the Wilsons.  I purchased one JL Fathom 113 and it was great.  I then added a second one, placed in the opposite corner diagonally facing each other and it really smoothed out the response.  I use a DBX subharmonic sythesizer, along with a Sony  TA-E2000ESD, as a separate remote volume control.  The Sony has a parametric eq that I filter down the 50-60 hz frequencies and turn my crossover point on the subs, as low as it will go. I come out of my line stage’s tape monitor output, so I can isolate the bass.  Because the Sony has a motorized dial volume, I can pretty much tell, where to set it on the clock dial.  When I turn my main speakers off, just to hear the bass level, most of the time the bass is at a fairly low level and is not overpowering.  I get an almost seamless contribution from my subs.  I can also turn my subs off, to hear what it sounds like, without the subs.  The difference is almost always very subtle, but can hear a definite improvement with the subs.  I built some hefty stands, 18” tall with metal castors, so I can easily roll them around the room, to establish the best position. I think the trick, is to set your sub volume, as to not make them shake the room.  They’re like a quartet, each contributing, but none overpowering the other. They definitely have their place in my system.  

Since you have both why not just try them both and use the one you like the best?

There are no speakers currently manufactured that " need " subs. If a person wants to add a little more foundation to the music they may choose to add a sub or two or one might suppose a swarm of subs. 

I'm using a single small REL t5si sub with my Harbeth P3esr speakers.  I moved it around the floor until I got a good sound.  Running the speakers full range and I keep the crossover on the sub set fairly low.  The sub volume is also very low.  It's a subtle difference, but the arrangement creates a bit more body in the bass.  The speakers are actually fine without the sub.

I use a different system for Home Theater, with a noisier subwoofer.

Remember that good subs don't simply add bass reinforcement, but contribute to the overall listening experience by adding life to the mix. Live concert halls and even studio mixed recordings have lower frequencies adding an ambient and more lifelike "feel" to pretty much everything, and although your speakers might not "need" this, I know I need it for things to sound like real music. My current Heresy IIIs are great at producing realistic sounding bass within their range, but really drop off at around 58hz or so...my subs take up the rest and the resulting overall low frequency coherency and "room charging" gets the mojo right.

After setting the low-pass filter, I use pink noise to set the levels of all my speakers, including the subs, to 75 dB SPL, then listen to a variety of recordings.  My goal is to not be aware of the subs.  A Velodyne SMS-1 bass manager sets crossover, slope, and acoustic room correction for the subs.

As an amendment to my OP, I did buy a pair of KEF Reference 1s.  Hope I don't regret it, given the LS50s supplemented by the HGS-10s sound so good even for large orchestrations.

db 

mcreyn’s response to s200cr’s statement about just buying speakers that don’t need subs:

" Why? The best speaker placement for imaging and bass are generally mutually exclusive!!!!! Are you willing to place 4 main speakers around your room at the optimal positions to minimize standing waves (ala a swarm setup)? Show me a full range speaker system that can go flat below 20hz that costs less than $10,000 a pair and is optimized for placement in the bass where the imaging is the best. The system in my office (a used set of Totem Mites and a Rythmik L12 for a total cost of $900) does that comfortably (when I say comfortably, it starts to roll off at 23 hz is and 1 db down at 20hz)."

Great response, mcreyn, I was about to post and make many of the same points before I read your response. I just want to add a few thoughts to further emphasize your thoughts: My opinion and suggestion is to approach the setup of your home audio system as 2 systems: a bass system and a midrange/treble and sound stage illusion system.
The first step is to get the bass sounding right. As I’ve stated previously, I believe buying and properly setting up an Audio Kinesis Swarm or Debra system is the simplest and most reliable method of achieving this if you have the funds ($2,500-3,000) and room space. But, for those on a stricter budget, here are my suggestions for optimizing bass in your room based on number of subs you’re able to afford:

1. No Subs/just the bass drivers in your main speakers- As mcreyn has accurately stated, the best speaker location for both imaging and bass response are highly unlikely, if ever, going to be optimized at the same room position. Full range speakers that contain bass, mid-range and treble drivers all in a single cabinet are, therefore, highly handicapped in their ability to provide good bass response and good imaging right from the get go.
Having a physically separate bass system that seamlessly integrates powerful and well defined bass response with physically separate main speakers system providing high quality mid-range/treble sound reproduction with a realistic sound staging illusion, even if there’s some bass frequency redundancy between the 2 systems, is an alternative solution that is highly superior in my opinion based on experience.

2. One Sub- With a single sub, unfortunately, the bass will be compromised because the bass will only be optimized at a single point in your room (your listening seat sweet spot) and the bass will not sound as good at other spots in your room. To optimally position a single sub, place the connected sub at your listening position/seat and play some content that contains several minutes of good and repetitive bass. Then, starting at the front-right-corner of your room, slowly walk counter-clockwise along the walls of your room until you find the exact spot where the bass sounds best to you. Lastly, locate the sub to this exact spot and then replay the bass content to verify the bass still sounds good to you when your seated at your listening position/seat.
     mcreyn, Isuggest you may want to try this in your single sub office system.

3. Two Subs- 2 subs will give better results than a single sub because, if properly positioned, any bass standing waves at your listening position may be reduced or eliminated and each sub is reproducing only a portion of the total content bass. This increases the capacity of bass volume, impact and dynamics/headroom. To optimally setup 2 subs, the one sub setup above is used for sub#1 and then sub#2 is placed at the listening position/seat and the same procedure is used to locate the exact optimum room position, continuing the search from sub#1 along the room walls counter-clockwise.

4. Three Subs- 3 subs will as expected give better results than 2 subs by further increasing the capacity of bass volume, impact and dynamics/headroom. But 3 subs, if properly positioned, will also begin to significantly reduce or eliminate bass standing waves throughout the entire room, beyond just those at the listening position/seat. Walking around the room, specific spots where bass response is perceived as less than optimal will be noticeably fewer with 3 subs when compared to 1 or 2 subs. To optimally set up 3 subs, just follow the procedure for 2 subs above and then sub#3 is placed at the listening position/seat and the same procedure is used to locate the exact optimum room position, continuing the search from sub#2 along the room walls counter-clockwise.

5. Four Subs- 4 subs are required for achieving sota bass response in any room. Acoustical experts have statistically identified that 4 subs in a room as the threshold at which the vast majority of bass standing waves in most rooms are reduced or eliminated, with any additional subs only providing moderate and smaller marginal benefits.
In summary, the more subs you deploy in your room, the fewer bass standing waves will exist in your room and, as a direct result, the better your in-room bass response will sound.
I don’t consider myself a bass expert. I just read all the material I could find on-line and rely on my years of experience of striving for very good bass response in my systems; beginning with no sub and progressing to 1, then 2 and 3. All of my systems sounded very good to me but the bass always seemed compromised to varying degrees.
Then I read scientific White Papers written by a a couple of acoustical scientists, Dr.Earl Geddes and Dr. Floyd O’toole, about their results experimenting with distributed bass array (DBA) systems in commercial and home environments.
It all made good sense to me but I was resistant at first due mainly to the cost and concerns about accommodating 4 subs in my 16 x 23 foot room. But, after discussing at length the Audio Kenisis Debra 4-sub dba system with James Romeyn. owner of James Romeyn Music and Audio in Utah, I decided to to buy the complete Debra system for about $3K with a free 30-day in home trial period.
It took about 4-5 hrs for a friend and I to set it up carefully following the progressive sub positioning method and routing all 4 custom speaker wires in the crawl space below my living room.
Still relying on the concept of building my system as 2 systems, a bass system and a mid-range/ treble and sound stage illusion system, I considered the reproduction of bass frequencies from about 20 to 40 Hz to be solidly in place and providing the foundation for placing the remaining mid-range/treble and sound stage illusion system atop it. I use a pair of older Magnepan 2.7QR 6 x 2 foot panels, driven by a pair of D-Sonic M600M (1,200 watts @ 4 ohms) run full-range for this purpose. Whereas the Debra system provides sota bass response virtually throughout the entire room, the main speakers require careful placement to provide an accurate and musical portrayal of the remainder of the audio spectrum and provide an optimum .sound stage illusion at the specific listening position/seat sweet spot.
A benefit of treating your system as 2 systems is that, once your subs have been positioned, your main speakers can be located completely independently for optimum mid-range/treble response as well as for creating an optimum sound stage illusion. After considerable trial and error experimenting, I was able to locate each panel so that all performance parameters were maximized; this resulted in my panels being locted about 4 ft. away from my front 16 ft. wall, spread about 7 ft. apart on center and slightly toed-in angling toward and straddling my listening chair about 14 ft. away centered n my rear 16 ft. wall.
We initially auditioned it on ht by playing a Bluray copy of the movie Fury, a WWII tank film with Brad Pitt. Our first indication of how exceptionally well this system reproduces bass was during the opening trailers of a soon to be released movie on Bluray, Whiplash, that contained a solo drum soundtrack, recorded direct to digital and played back at 24 bit/96 Khz hi-resolution .digital through my Oppo 105 Bluray player., that was a driving beat that built to a final crescendo that had my friend and I staring at each other in disbelief with how spectacularly real and ’right there in the front center of the room’ the drum kit was perceived to be by both of us.
The WWII tank and heavy machine gun battle scenes in the movie, Fury, were also portrayed, with the assistance of my 5 other full range speakers in Dolby Digital 5.1 (5.4?)Surround Sound format, in an extremely realistic manner.
After the movie, we also auditioned a wide variety of music stored as 16 bit/ 44 Khz files of ripped CDs and some hi-res 24 bit/96 Khz WAV music files,stored on my NAS hard drive.
I find the entire music listening experience as being very immersive, with the width and depth of the sound stage illusion varying slightly in size, stability and overall realism depending on recording. I’ve noticed those recorded direct to hi-res digital are generally significantly superior in all 3 of these qualities.
To be clear, I’m not stating you cannot attain very good full range sound performance in your system using no or 1 to 3 subs.
What I am trying to convey is that the science is correct, utilizing 4 subs seems to pass a threshold that, due to the vast majority of bass standing waves either being reduced or eliminated, allows for bass response that is both powerful and well defined that far exceeds the bass performance that I was ever able to achieve with fewer than 4 subs in my room.

Sorry this post was so long,
Tim