Do you use a Subwoofer when listening to stereo?


I thought using a 12 inch b&w asw 2000 sub would b good to allow my b&w 804 d3’s to better handle freq above 80 hz (ie. benefit from sharing burden).  I am not sure this is prudent as my well powered 804s can probably handle those lower frequencies just fine, and may make them sound better vs cutting them off from flowing thru the 804s.
My Stereo listening is done by streaming thru a nucleus connected via usb to a chord Hugo tt2 and then to a marantz 5014 via coaxial, then to a McIntosh mc255 and then off to speakers referred to above

 Does excluding sub from stereo make sense?
emergingsoul
Post removed 
Does excluding sub from stereo make sense?
No. Not even. The key to really good bass is having it come from many different locations. This means for one thing you want to run your 804s full range. Then use as many subs as you can. I used just one for a long time. Then four. Now five. https://systems.audiogon.com/systems/8367 Never even dreamed how much better bass could be until my DBA.

" Does excluding sub from stereo make sense?" Only you can answer that question. In my experience many systems benefit from having properly integrated subwoofers. Properly integrated subwoofers improve the "spatial" information within the recording.  
Treat your room appropriately first. Many full range owners who are looking for more bass find this solves their problem so much they no longer consider a sub.


The problem is that the room has a dimension and bass waves will reinforce at certain frequencies and cancel in others. So unless your bass traps are actively able to move about the room as the bass notes change they will have little effect. DSP doesn’t work because it tries to make your amplifier put out more power at one frequency and less at another. But when you are dealing with a standing wave you might be able to kill a bit of bass bloat at one frequency but you can put as much power as you want into the bass nulls and the waveforms will still cancel. So its only slightly more effect than bass traps.


If you really want to deal with this problem, the elegant way to do it is to use a distributed bass array which can break up standing waves, resulting in evenly distributed bass throughout the room. Do do this, you take advantage of the simple fact that below about 80Hz in all but the largest rooms, the ear cannot detect where the bass is coming from so you can run the bass in mono. But it is important that the subs do not reproduce anything above 80Hz; in this way they will not attract attention to themselves. You’ll need at least four subs to do this right. They need to be asymmetrically placed in the room and therefore do not have to be aligned with your Harbeths. One sub system called the Swarm (www.audiokinesis.com) is also the most well-known sub designed for this purpose. To minimize their size they are designed go directly against the wall and take advantage of the room boundary effect, to go flat to 20Hz.


This is basic physics- in almost any room there will be standing waves. I've seen audiophiles fight them for decades- only to find out that by using a DBA that suddenly all is well. If you want an elegant and effective way to solve this issue, this is how its done. 
My Stereo listening is done by streaming thru a nucleus connected via usb to a chord Hugo tt2 and then to a marantz 5014 via coaxial, then to a McIntosh mc255 and then off to speakers referred to above
So, you’re running a $5500 DAC into a $1000 AVR??? to an $8000 amp and $10,000 speakers? Dude, preamps matter for stereo listening!!! Forget worrying about subs and start researching decent stereo preamps pronto. The Marantz is absolutely killing your 2-channel performance.


Depends somewhat on the type of music you listen to and your age. I find most of what I listen to I don't need a subwoofer but my speakers will go down to around 24hz  measured with REW 
I like functionality of avr where I can view tv screen while listening to stereo.

its very easy with the marantz avr.  I just press one key on remote to change source and that’s it ( ‘video select’ is their version of independent service).  Of course all this follows pressing play on roon.
not sure if other higher end preamps will work this well.

I use 4 subs in my main system.  I have 3 smaller systems.  Each of them has a subwoofer.  Where space permits, more is better.  

I have to agree with the person that said to consider ditching the receiver before you do anything else.  Get a preamp (or an integrated amp and ditch the Mac amps also) that has home theater bypass and use it for two channel listening and limit the Marantz to home theater use.  Then start adding some subs.
Why don’t you like McIntosh? Due to multi Chanel amp? Mac does a great job with amps under one roof.  That’s why the don’t sell smaller mono amps, the don’t need too.

i likely will get a stereo preamp and need to explore the process of switching back and forth between stereo and ht, ie. How many steps involved.
I'm an old school guy. I have a reasonably priced Paradigm 10" subwoofer parked to the left of my out-in-the-room NOLA Boxers, set up against the back wall but not too near the corner. I used my ears and a stereo test CD to match levels with the rest of my system and minimize boom. My system doesn't go all the way down to 20hz but I figure I'm able to enjoy a pretty good 30.  Bottom line (heh-heh) -- the subwoofer significantly enhances my modest system. Not only does it provide bass, it increases the size and believability of the soundstage.
i likely will get a stereo preamp and need to explore the process of switching back and forth between stereo and ht, ie. How many steps involved.
Not much to explore fortunately. If you get a preamp with a HT bypass feature you just push one button to switch between HT and stereo and that’s it, and when in stereo the Marantz is completely out of the signal path. I did this for years before I got a dedicated listening room and it works beautifully — best of both worlds really.

So, very quickly on how this works so you see how how absurdly simple this is — you just need one pair of interconnects and run them from the front L/R preamp outs from the Marantz into the HT bypass input on the stereo preamp and hook the line outs from the stereo preamp to the inputs on the Mac and you’re done. That’s it. Literally takes two minutes, and you won’t believe how much your 2-channel performance will improve — the preamp sections of most AVRs are just crap, relatively speaking.

BTW, this also works fine if the stereo pre doesn’t have a HT bypass and still involves the same hookup and pushing one button and adjusting volume on the pre to a predetermined level for watching movies/TV (can go into more detail if you might go this route) and that’s it. Start shopping for a good stereo preamp — it’ll be one of the most significant upgrades you’ll ever make. Hope this helps, and best of luck.

Yes
Yes
The only "sense" in this game is whatever sounds best.

Lotso luck finding speaker outputs on a preamp.
You push a button on the remote. I use an C2500, and a MX121, source vary from a TT, SDAC, CD, Stream, into MC275 and Class Ds, or Carys and Class Ds. Pure heaven... Easy as could be.  

Mac made a LOT of smaller monoblock... 20, 30, 40, 50, 60, 75, 100s

All were older, except the MC75, and they are still in production...

ALL of their amps are know for plenty of UMPH..

Most of music until  hip hop / rap didn't have that much sub, they were pretty much cut at 40-50 hz down, the old 78 stuff 60 hz and below.
All of my old Reel to Reel stuff is cut at 40. Big band, jazz, and country western, were all the same..

You can add BASS to the mix though...and really liven the joint up...
What most music listeners listen to is NOT sub heavy, it's bass heavy.
Subs muddy most good stereo system up because they're set WAY to high on the XO. 80 hz is the highest. Cut the bass on the mains where your subs stop.. Simple... Ya need a few though to get it Everywhere.. I don't.. Where I'm listening is just fine.
Junior (my rabbit) thanks me too. :-)

Regards
"Does excluding sub from stereo make sense?"

Only if your main speakers are full range.  
soix,
thanks.
when you transfer signal path to stereo amp, does the tv continue to display?  Very important to watch vote tallies for next 12 weeks while listening to fine music.
Why don’t you like McIntosh?
If that was directed at me, I did not say that I don't like McIntosh.  I'm not familiar with your amp, but it looks like a nice one and should have more than enough power to drive your main speakers.  If you like the amp, then get a preamp with home theater bypass.  As another poster described, it's super easy to switch between the preamp for 2 channel listening and back to the Marantz for home theater duties.

atmasphere nailed it.
I use two I wish I could run 4 .I have mine come in very low 
Atmasphere did indeed nail it
when you transfer signal path to stereo amp, does the tv continue to display?  Very important to watch vote tallies for next 12 weeks while listening to fine music.
Yes.  You’ll connect the Chord into the stereo preamp (as God intended) to play 2-channel, so you’re free to do whatever you want with the Marantz and the TV independent of the music. 

It sounds to me that Atmosphere also agrees with Vandersteen
I use a sub (12" peerless XXLS subwoofer + KG5230 amp) occasionally when I listen to stereo. Certain music sounds good with little bit more bass added even though my full range speakers go pretty low. 

Yes I do. I have mine crossed over at 50-60 hz range.
Yes on the sub/subs. Regarding the DBA, rooms vary and a DBA may not be practice for whatever reason. Only you can decide. But overall a sub system with stereo is excellent. Regarding your tv/stereo situation... simply run a digital (optical is good) out from your tv to your dac and out to your pre amp. HDMI sucks, and if that is the only reason you are using your Marantz is the HDMI hookup, you can do better. Ultimately, what do you want out of your system? The best possible stereo music playback, or TV audio? That will tell you what route to take...
A properly set up sub can give you increased clarity in the mid range, more detail in the bass, a larger soundstage and increased center focus. Wouldn’t be without one.
Are your B&W 804 D3 speakers a part of a home theater system and positioned in that general fashion?

Are you currently using the LFE 80 Hz connection to your ASW 2000 subwoofer? 
No, but I would not be adverse to trying one.  I have a very inexpensive one on my TV surround sound system and it seems to be OK.

Cheers!
Post removed 
I am using two HSU ULS-15s to augment a pair of Klipsch Cornwall IVs. I am running the CW IVs full range and bringing the sub in @ 35 Hz. Excellent integration and it only barks when the occasion calls for it.

Oz


I have sub set at Lfe 120 hz thru settings, no special connection.  Not sure how often lfe freq are used by sound engineers.  Is this a big deal?.
Does excluding sub from stereo make sense?


     No and here's exactly why in your case:
     Your B&W 804D3 speakers are very high quality, expensive and have a rated bass output extension down to the audible lower limit of 20 Hz.  However, it's highly unlikely that you're experiencing and enjoying bass response this deep at your listening position because the woofers, that are responsible for launching these very low frequency sound waves into your room are permanently affixed in their cabinet. This rarely discussed design flaw is true for any speaker, no matter its design type, that has a rated bass extension deeper than about 80 Hz. 
     This permanent affixation of bass transducers in a speaker means they're not capable of being independently positioned in your room, and in relation to your listening position (LP),  which is required to optimize the perceived bass response at your LP from 20 Hz up to about 80 Hz.  The truth is that, even if the bass transducers in a pair of speakers are launching pristeen deep bass sound waves into the room, it's highly unlikely these sound waves will reach the LP in the same pristeen condition.
      The explanations for this reality are detailed and best understood via physics and how humans perceive sound, especially below about 80 Hz.  The deeper a sound's frequency, the longer its corresponding full cycle sound wave and the higher a sound's frequency, the shorter its corresponding full cycle sound wave.  Think of sounds, and their corresponding sound waves, as a continuum from long and deep to short and high.  For example a 20 Hz full cycle sound wave is about 56' long and a 20,000 Hz full cycle sound wave is a fraction of an inch long. 
     It's important to know that the longer bass frequency sound waves have omnidirectional radiation patterns and the much shorter midrange and treble frequency sound waves have highly directional radiation patterns.  It's also important to realize that the longer, omnidirectional sound waves/tones, typically below about 80 Hz, are not localizable (individuals are able to determine their specific position in space) by humans and that the much shorter, highly directional sound waves/tones, typically from about 80 Hz up to 20,000 Hz, are highly localizable by humans, and progressively more easily as the frequency increases.
     In addition, there are some peculiarities in how we humans perceive sound and sound waves:

- We don't even perceive a sound as existing at all until our ears detect a full cycle sound wave at a specific frequency, our brains process the input from the ears and the brain creates the perception of the sound at that frequency. Anything less than a full cycle sound wave being detected, results in no sound being perceived. 
      This fact becomes especially important with bass perceptions in a finite room, since some full cycle deep bass sound waves may exceed the dimensions of the room.  This requires the sound wave to bounce or reflect at least once off of a room boundary (floor, ceiling or wall) before the full cycle bass sound wave exists in the room, is detected by our ears, processed by our brains and the perception of a bass tone at a specific frequency is created.

- Since we generally can't localize bass frequency sounds below about 80 Hz, we perceive all bass below about 80 Hz as mono, which means no true-stereo deep bass exists below about 80 Hz.
     I stated no "true-stereo deep bass" because we are capable of perceiving a form of stereo deep bass thanks to our amazing brains. Our brains are able to perceive a fundamental deep bass tone below 80Hz,  often reproduced by a sub and unlocalizable, as mono and perceive the fundamental deep bass tone's natural overtones or harmonics, which often extend beyond 80 Hz, are often reproduced by the main speakers and are localizable, in stereo. 
     Our amazing brains are then capable of associating the mono fundamental tone with the stereo overtones or harmonics and localize the deep bass tone.  The result is a form of stereo deep bass that I believe needs to be distinguished as something other than "true-stereo deep bass".  For you, this means you can incorporate a sub or subs in your system and you still perceive a stereo sound stage illusion that is equal to, or more likely better than, your current one.

     The next facet of acoustic sound physics it's useful to understand is that all sound waves, at all frequencies, launched into your room by either speaker or sub drivers will travel outward and continue to bounce or reflect off of room boundaries (floor, ceiling and floor) until they are absorbed or diffused/scattered by acoustic room treatments, run out of energy and naturally decay or they collide with another sound wave.   
     Whenever these sound waves collide with each other, it creates what's called a "room mode" at the specific room location of the collision.  These room modes/collisions happen all the time with midrange and treble frequency sound waves and, in an untreated room, are normally perceived as 'airiness' or 'liveness' qualities, which many individuals perceive as enjoyable. 
     However, these midrange and treble room modes/collisions also negatively affect tonal accuracy, stereo details and stereo imaging.  But these midrange and treble room modes affects can be reduced, mitigated and controlled to an extent through strategic deployment of sound wave absorbing and diffusing acoustic room panels/treatments. 
      These room modes/collisions happen often with bass frequency sound waves, too. In an untreated room, however, bass room modes are normally perceived as bass overemphasis (a bass peak),  bass underemphasis (a bass dip) or even a bass cancellation (a bass null).
      But these bass room modes affects are much more difficult to reduce, mitigate and control than midrange and treble room modes.  The required bass trap room treatments are larger, more expensive and can't always be aesthetically placed at the specific room position they're services are needed. 
     Okay, the preliminary topics have been covered on this tome, and it's finally time for me to tie this whole thesis together and get to my recommendations for your specific circumstances.
     Yes, I could have saved  a lot of my time and yours by just stating I agree with atmasphere's earlier suggestion of the Audio Kinesis Swarm 4-sub distributed bass array (DBA) system as an ideal solution but I thought it was more valuable with you having a good understanding for my reasoning for my suggestion.  Here's an Absolute Sound review of the AK Swarm system that gives a very good description of what to expect:

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

     I use the very similar AK Debra 4-sub DBA in my system/room and can state with certainty, if you have the available room space for four relatively small (1'x1'x2') subs in your room, that you'll be amazed by the near state of the art bass performance of this relatively affordable ($3,200) complete kit bass system.  It's attractive in your choice of woods, the subs would be positioned around the perimeter of your room and are easily concealable and the bass integrates seamlessly with virtually any pair of main speakers. 
     I also believe your very high quality main speakers deserve an equally high quality 4-sub DBA system.  I think you could probably come close to the Swarm's performance by utilizing a pair, of properly positioned and configured, high quality subs.  However, the very good bass would be restricted to a single designated listening position rather than throughout your entire room with the Swarm and the Swarm will likely cost a few thousand dollars less as well as being easier to set up and configure. 

Best wishes,
   Tim
noble100
thanks so much. awesome

so maybe setting up the speaker settings to large (rather than small) makes more sense so that it completely opens up the main speakers. Why bother restricting bass on mains, and then set the subwoofer separately via settings on back of cabinet..

The sub array setup may have merit in a larger room. My room is 12 x 16 with 7 1/2 ceilings. The extremely large asw 2000 from b&w with 12 inch driver set lower would seem more than adequate. I do need acoustic panels.




Hello emergingsoul,

     Are you using an audio/video receiver to power your main speakers?  If so, yes you should set the front l+r speakers (your 804Ds) to "large" so they run fullrange.  Why do you have them set to "small"?
     You should also connect your asw 2000 sub to the "sub out" or "LFE" output on the back of your A/V receiver and optimally position your sub in your room, and in relation to your listening seat using the 'sub crawl method (google it). 
      Then adjust the volume, crossover frequency and phase controls on your sub until the bass sounds best to you.  The goal is to set the sub's volume and crossover frequency as low as possible while the bass still sounds very good to you.  
      Give this a try and report back with your impressions.

Later,
 Tim   
Having heard and loving the sound of B&W, always hearing that they do produce the amount of bass they say they do:

there is no way I would add a sub to those speakers

except

IF I felt the PORT was a bit muddy,  then sending low bass to self-powered sub only; thus out of both the main amp and speakers, might be preferred, that is what I suggest you listen for.

IF I was trying to fill a too large space with low bass.

I have been using a pair of Vandersteen 2Wq subs with my mains for about 12 years.  I wouldn't want to listen without them.  Deep, clean, powerful bass makes listening more involving and leaves more power for my mains.  The battery biased external crossovers keep things transparent.  Bass integration with these subs is superb, and in my room, corner placement works best, as they were designed for corner placement.
Hmm. Could someone explicitly confirm what I read here is true: that, even if I use twin-subs, I should set the bass on my speakers to 'Large'?

My setup: a Denon X3700H AVR (used as a pre-amp) --> Parasound A21 --> Focal Electra 1038Be + Twin ML Dynamo 1000w subs.

Currently, I have main speakers set to small with crossover at 60Hz.

I've read elsewhere that this is the way to go, unless one is using very powerful amps. While my A21 amp is rated to 250W with 60A peak current capability, the 1037Be (close enough to 1038Be) speaker measurements on Stereophile.com show that my speakers may be quite difficult to drive at <60Hz frequencies (a combination of low impedance and -ve capacitive phase angle).

TIA.
Hmm. Could someone explicitly confirm what I read here is true: that, even if I use twin-subs, I should set the bass on my speakers to 'Large'?

If you really care about accurate integration with your speakers, connect the subs using the speaker outputs on your main amp. Now if all you care about is "more bass", then do what you planned.

Oz


Ozzy62: Unfortunately, my subs don’t have speaker level inputs, only line level.

I don’t care about ‘more bass’ - just want to integrate subs as well with the speakers as I can.
I had only two subwoofers with full range speakers (Salk Songtowers) so can't speak to having 4+ subs.  When I finally finished treating the room and locked the position of the primary stereo speakers, I decided to go without the subs.  The Salks were now putting out, what seemed to me, palpable sub-bass. You know, the feel-it-in-your-chest...coming-out-of-the floor kind of bass.  The only thing was that it was soft.  It was big but softer compared to the subs.  But it felt more organic to me and I didn't have to concern myself about it when I changed records. I don't miss the subs...but I also don't know any better sub solution.

At some point, I just didn't want to keep concerning myself with bass all the time. I think before you get into multiple subs, you got to nail the mids and the highs...an by that I mean the imaging. Great imaging is way more rewarding than great bass. Sometimes I think we chase great bass because the imaging isn't doing it for us.

Anyway, I'm in a different house.  It's been a year and I haven't locked down the imaging yet.  It's not a dedicated listening room either which make it tougher.  But I will keep exploiting the room...
I've used sub woofers for probably 25 years or so.  I enjoy what they add to the "musical experience".

Having said that, if you decide to add a sub or two to your music audio system, please be patient.  Integrating subs can be a challenging and frustrating experience as the acoustics of the room they live in might require a lot of time and money to get the needed treatments.

In my last house, my 2.0 system sounded fantastic!  The bass that my main speakers had was excellent, just not as good as a sub would provide in the lowest two octaves.  I added a pair of excellent subs, which came with microphones and an internal app to "tune" them to the room, but the room would add a single bass note, regardless of what the bass player was playing.  I eventually bought a special microphone and a special piece of software to help me purchase and install 10 bass traps, to mostly control the errant response from the room!  I had challenges with other subs in other listening rooms, but nothing as frustrating as this.

We are three weeks from settling on a new home, with a dedicated listening room, fingers crossed that the subs will "behave" in their new digs.
@emergingsoul 

Im not sure you ever said whether the sound/bass you are getting from your mains is satisfying?

moving lower frequencies off the mains may allow you to play louder... may result in lower distortion... may or may not result in an audible improvement. 

Most likely a sub/subs will improve the slam factor if properly located and dialed in. 

So, it all comes back to the question... are you happy with your sound with no sub?
I’ve been spending the past couple days tuning a pair of REL S812s. It’s challenging because I have a mode around 60-70Hz, presumably the floor-ceiling mode. After a bit of tweaking, I think I’ve finally gotten the crossover low enough to avoid audible mode over-excitation. I can still see the mode on the RTA but I don’t notice audible distortion 

I set the crossovers for my usual listening SPL. I think if I played much louder, the mode would be more audible. 
Hello hsw,

     Are you stating that you're using a pair of subs and you're hearing or measuring a bass mode between 60-70 Hz at your listening seat? If so, this just means that at least one of your subs are positioned poorly in your room and in relation to your listening position (LP).  Apparently, your LP is in close proximity, or smack dab in the middle of, a bass room mode which is heard as a bass peak, dip or null.
     When utilizing 1 or 2 subs in a room, and the 'sub crawl' method is used to properly position them in the room and in relation to the LP, one of its major advantages is that this method ensures that there are no bass room modes in close proximity to the LP.
      I suggest you google the 'sub crawl method', utilize it to sequentially locate both of your subs.  Then adjust the volume and crossover frequency controls on both to the lowest settings you can while still maintaining bass performance that sounds good to you (it's solid, powerful, smooth, fast, detailed, dynamic, tonally accurate and it sounds natural).   Only once these steps have been completed,  would I recommend measuring your room to verify results.
     One or two subs in a room, provided they are optimally positioned in the room and in relation to the LP utilizing the sub crawl method, are capable of providing good bass performance, that is bass mode free, at a single designated listening position.  If you walk around the room away from the LP, however, you'll notice there are still numerous bass modes at specific spots in the room, heard as bass peaks, dips and nulls. 
    Utilizing 4 subs in a room in a distributed bass array (DBA) configuration in a room are also capable of providing good bass performance that is bass mode free.  But its main advantage is that it'll do so throughout the entire room and not just at a single LP. 
     If you walk around the room away from the LP after a 4-sub DBA  is installed, such as an Audio Kinesis Swarm or Debra DBA system, you'll notice there are no bass modes of any type perceived at any specific spots throughout the entire room.  

Later,
 Tim
    
    
No, and I never will. Now I do use one in home theater and that's where it stays. I'm not into the boom boom boom when listening intently to my stereo. 
No, and I never will. Now I do use one in home theater and that's where it stays. I'm not into the boom boom boom when listening intently to my stereo.
You might want to open your mind a bit on this.  Properly integrated subs can positively transform a 2-channel system.  Companies like Wilson, Vandersteen, etc. don’t offer subs just to add “boom boom boom.”  IME, once you’ve heard a system with good and well-integrated subs you don’t want to listen without them anymore.  They add much, much more than “boom boom.”

No, and I never will. Now I do use one in home theater and that's where it stays. I'm not into the boom boom boom when listening intently to my stereo.
With 4 subs there's no "boom boom boom" in my room.  If that's all you're hearing when you're listening to movies you could benefit from more subs and/or better setup and/or room treatments.  It's kind of like saying "I don't play vinyl because of the noise".
A. TWO Channel Mode/Use of Home Theater:

a1. AVR sends full frequency signals out front left and front right ONLY.

a2. no center, no surround, no sub signals from the AVR outputs.

a3. ALL Imaging is Phantom, created by AVR front left and front right. True whether you do or do not have a sub or two included in 2 channel mode. More below.

a4. programs that ’arrive’ in surround may/often sound better if you try/change to 2 Channel, thus more important than you might think.
......................................

B. SUB(s) ON SURROUND ONLY (sub out, mains only for 2 channel (video or music).

b1. choose mains with enough bass when in 2 channel mode

b2. single sub, non-directional can more easily be successful when on only in surround mode

b3. easiest wiring, simply sub out of AVR to sub, done.
........................................

C. SUB(s) ALWAYS ON (any Surround AND on for 2 channel).

c1. stereo pair of subs, directional, near mains

c2. all imaging is Phantom, any location of low bass fundamentals and overtones will reveal directionality, which you WANT.

c3. Now you need to take your AVR’s front left and front right to a CROSSOVER: ALWAYS send some to the sub(s); ALWAYS send the rest to the mains.

c4. Crossover can be separate component OR built into the sub(s). IF crossover is in the sub, then you have to get to the mains from the subs. This is another reason to use a stereo pair of subs located with the mains.

c5. Any crossover should be ADJUSTABLE for 5.1 or 2 channel

c6. self-powered subs produce the bass, which means the AVR’s amp and front speakers have an easier job to do

................................

D. SIZE OF MAINS SETTING

d1.Telling AVR the size of your mains effects surround modes only. It always sends full frequency out front left and front right in 2 channel mode.
....................................

E. CENTER CHANNEL SPEAKER REQUIRED for ANY SURROUND MODE

e1. the programs coding, and the AVR's coding removes all the DESIGNATED audio information from the front speakers. Thus, a CENTER SPEAKER is definitely needed, no matter how good you mains are. You cannot make Phantom Center Dialog if the information does not exist in the front outputs.

e2. center channel is ALWAYS OFF during 2 Channel Mode, imaging from front and subs more important.



emergingsoul:
" noble100
thanks so much. awesome

so maybe setting up the speaker settings to large (rather than small) makes more sense so that it completely opens up the main speakers. Why bother restricting bass on mains, and then set the subwoofer separately via settings on back of cabinet..

The sub array setup may have merit in a larger room. My room is 12 x 16 with 7 1/2 ceilings. The extremely large asw 2000 from b&w with 12 inch driver set lower would seem more than adequate. I do need acoustic panels."

Hello emergingsoul,

     The choice of whether to operate one's main  L+R speakers full range. or restrict their low frequency output, should be based on the main speaker's efficiency, their rated bass extension, the specs of the amp driving them, whether a sub or subs are going to be employed and personal preferences.  
    In your case, for example, I believe your speakers are sufficiently efficient, have a sufficiently deep rated bass extension, your amp has sufficient power and current capacity and your going to employ at least 1 sub.  This means everything's a go for operating your main speakers full range and it just will depend on your personal preference. 
     I suggest you change your main speakers setting to large (rather than small), optimally position your sub in your room using the sub crawl method and setting your sub's volume and crossover frequency controls as low as possible with the bass still sounding very good to you.
      Then it's up to you concerning which system set up and configuration overall system sound quality you prefer.

Best wishes,
  Tim