Subwoofer

i think the dual driver helps with room nodes and if you only use one subwoofy

KEF dual driver subwoofy gets good reviews

https://international.kef.com/products/kc62-subwoofer

I think this SVS is in my future

https://www.svsound.com/products/3000-micro-subwoofer

The issues with no choice in placement is dealing with room integration. Any subwoofer which is big enough will do IF you have the appropriate measurement and EQ gear.

Personally a huge fan of HSU but I use mine with a miniDSP or the room correction built into my HT receiver. 

What’s your budget, and any size limits/restrictions?

I don’t think one subwoofer is a good idea, in general, in addition to speakers with reasonable base. Two can enhance and enrich the sound. One will just muddle it while it will sure add the thump, which I will need for 3 minutes a day.

(and I wish it weren't the case, I tried for almost a year now with different (single) subwoofers)

I think grislybutter is right...

I bought a subwoofer years ago because my MIssion Cyrus never go down 45 hertz really...

With an organ music album it is a pity...

But the sub alone dont cure the problem and worsened it because the unbalance it created...I sold it on the spot... :)

I think it takes more than one sub  to balance the system and the room...

 Sadly at first but fortunately at last , my headphone replaced my dedicated room now because i sold my house... My headphone go so low under 30 hertz that i feel the wave with my body and feet by bones resonance and it is like the owgan was in my room... No sub is needed...And my new headphone beat my past speakers in their well tuned room..

Tekton 2-10, 4-10 or 6-10…. Whichever suits yer fancy and WAF.

thanks @mahgister I hope you are enjoying the music whichever ways, maybe nearfield listening with speakers is an option too!

I can assure you the Akg K340 are now optimized and so good i will never go back to the difficult task to tune a room... I dont need because  the three dimensional "out of the head" soundfield of my headphone beat my past speakers or rival them  ...

The K340 is unique headphone the most different designed headphone ever compared to any other... Read about it...

My best to you and your family...

thanks @mahgister I hope you are enjoying the music whichever ways, maybe nearfield listening with speakers is an option too!

Give SVS a call they are very knowledgeable and will walk you through there product line to fit your needs.They also offer a trial period so you can send it back if it doesnt work out.

Good luck

To have one to three subwoofers work to their integration’l potential at your listening position its imperative to preform the subwoofer crawl to map out your rooms bass mode standing waves (optimum subwoofer positions).

https://www.youtube.com/watch?v=AV3oLLMgS-M

Another excellent option would be to look into ’distributed bass array’s’, Swarm.

A reluctant suggestion would be -6dB sub-bass speaker. Their dramatic frequency roll off may not excite your rooms modes, expanding location possibilities. Hopefully still provide a modicum of lowish frequency reinforcement. Good luck with your search.

You can usually make a single sub sound great in one listening position. Not a problem.

Multi sub systems smooth out room nodes so that bass can sound even handed and non booomy in more locations.

That said I’ve EQ’d bookshelves enough that I listen to them more often sans subs.

The only single sub that I would consider is the Vandersteen Sub 3.

I has an internal graphic equalizer, so you can tune it to the room. Unfortunately, not as inexpensive as other routes, but you get what you pay for.-Especially when you consider Vandy subs like the 2w are still working after 30+ years.

Bob

+2 for what @grislybutter said.

Integrating a single sub (which is how I started), especially if used in a 5.1 system as well as 2 channel can be challenging. 

For 2 channel I think it's helpful to think of the sub as a low-bass extension of your mains. So get a sub that is designed for that application and place them near each speaker. On the outside and a few inches behind is a good starting point.

It's really not that different from speakers with an integrated/powered sub, but I'd argue better if you get the right combo. Then just experiment with gain and crossover.

FWIW I use  I use two REL T/x9s which I think are very good value for the money but there are several brands that will do the job nicely. Pics in my profile if interested.

@mahgister 

Glad to see you are here again seemingly healthy. At our ages, you never know when one may have passed.

And yes, two subs is mandatory for quality stereo listening.

I used successfully use a single sub for about 15 years.

With only one sub, it's important to remove the sub range from the mains. AND have sufficient drive from the sub.

Most subs have inadequate controls to integrate properly. You must have variable crossover frequency and slopes, continuous phase and polarity inversion.

You can get away with a less capable sub by setting the controls to minimal, e.g. highest crossover and using miniDSP or other capable crossover. I do not recommend using the miniDSP internal A/D so either feed it digitally or only use it for the low end only, feeding the mains with a passive analog XO to roll the bottom octave @ 6dB/octave.

See ieLogical SubterraneanHomesickBlues. There useful links for room analysis and other information.

Thanks for your kindness ...

 My very best to you....

@mahgister 

Glad to see you are here again seemingly healthy. At our ages, you never know when one may have passed.

Hi I just purchased and installed two subs tonight!  They are Pyle 8" down firing that I got off Amazon for $125/each.  I used two because my mentor has two at his place that are on at a very low volume and cross over but what they add is a deep soundstage. I think having bass behind the speakers creates this.  I used male to female spliters and line out of my pre.  It makes holographic deeper sound stage. It is amazing. JH

Added an SVS micro 3000 (for dimensional reasons) to khorn-tube integrated system and, at lower volumes, it made a tremendous difference.

I intend to add a second one and hope the SVS app will be up to seamlessly integrating 2 subwoofers.

Baloney...I used one REL Q150 for years and it sounded great, and still use that one now along with a Q108MK2...still...one properly adjusted sub can work beautifully in any room.

@mahgister , it is good to 'see' you again...*vbs*

As one who's lived through both of the '60's', we're becoming rare instead of being merely 'well done'....;)

As for 'subbing it', a single self driven 8" for the moment, considering an array of 4; 2 - 8~10" left & right 'front", 2 - 6~8" L & R 'rear'...although 'placement' and levels subject to measure and taste....self-driven, perhaps...

All of which subject to the vagrancies of time, space, and budget....I need obedient clones....*L* 

I second the suggestion of a twin driver sub, I recently went from an old rel stentor III to a studio III. night and day better, smoother bass response at the listening position.

Find an audio buddy who will loan you a sub.  Install it in your "only" location, and make sure it isn't a "suck out" node in your room at which all low freq disappears, or a node which exaggerates low freq regardless of what adjustments you make.  If either of those conditions persists, forget the sub and be thankful you just saved yourself a bunch of $$.

What’s your budget ?  Both JL audio, and Rel have a stacked model 2 in 1 space 

@grislybutter - agree totally

I've just added 2 Rel S812 Subs to compliment my Kef Ref 5's.

My hifi buddy Rod uses 2 subs with his Wilson Sasha Daws and when I asked him to turn them off I was quite surprised at the difference so, I experimented with my (old) Kef TDM45 sub on my system. I could see the potential but nothing like the benefits shown on Rods system using 2 subs. He kindly bought his Rel S5 subs to my house and then I realised the potential. - I had to buy some!

All my speakers are Kef so I was drawn to them first but I don't think you can connect them using 'high level' inputs directly from mono amps so that put me off. Also, after watching many John Hunter videos I thought that Rel was the way to go. they only make subs ... right?

anyway, bottom line is I have been well pleased. Bottom end bass has obviously improved but to me the most pleasing aspect is the weight now given to the mid bass and vocals and especially the guitar. Listening at lower volume levels is far more enjoyable as well, much more overall presence.

so, if you can, find a way to integrate two subs - you won't regret it

good luck

@markprice 

glad to hear you mention how adding subs has not only added bottom end but has enhanced all the sound. This has been my results as well. I listen to any music eith guitars and find a well integrated sub bring weight to the guitars and the vocals and the drums. I crossover at a higher rang than most as I like to have the sub help with those midrange frequencies as well. To the op yes two or a full array is always better but one will still sound great when set right. 

Bass play a great role enjoying the music...Even for localization ( phase angle) and imaging and soundstage...

And hearing tuba clearly and deeply and organ bass note is like , time to time making love with a plump woman and not always with an anorexic, an another cosmos of love or sounds... :)

One sub only , everybody say it, is very difficult to balance ( impiossible for me in my experience)...

You are spiritually and syntactically irreplaceable here... I am glad to spoke to  you again...

@mahgister , it is good to 'see' you again...*vbs*

As one who's lived through both of the '60's', we're becoming rare instead of being merely 'well done'....;)

As for 'subbing it', a single self driven 8" for the moment, considering an array of 4; 2 - 8~10" left & right 'front", 2 - 6~8" L & R 'rear'...although 'placement' and levels subject to measure and taste....self-driven, perhaps...

All of which subject to the vagrancies of time, space, and budget....I need obedient clones....*L* 

+1 on calling SVS ... they can help 

And great to see @mahgister ​​​​and @fuzztone in same discussion two of my favs!! 

Given your limitations and speakers it might make sense to try the KEF offerings as they have settings to support non-optimal placement. The KC 62 might be a bit small for that room, the KF92 might be a better choice. 
 

I have LS50’s, and one sub is better than no sub. Yes, two might be better, but not required to improve your sound. 
 

One sub is very hard to put in a musical synergy with the speakers...

But if someone want only boom boom sound , it is very easy to plug it...

I plug mine few minutes and sold it... 😁 because i could not think how i would make it "musically integrated" ... i think that it must takes 2 ...

A balance sound is not a boom boom sound added...

But my short experience with ONE sub  ( Kreisel K9 ) was not happy and i could not figure out a way to integrate it "musically"  ...

But once this is said i am not a sub woofer specialist at all...But i love music and i hate boom boom... Perhaps i am wrong and there is a way in some room to do it musically with ONE sub... We must ask to a sub-woofer specialist for confirmation or debunking ...My intuition is location and room dimensions are very important for this problem then there is no absolute rule and in some case one sub can do the job perhaps... In most general case i think it takes more than one...

@jpwarren58 

I also have KEF speakers and wanted a subwoofer. My solution was to put an SVS 2000 Pro on the back wall, about six feet from my listening spot.  Their software is great and it sounds seamless.

All the best.

I have two subs, but typically only keep one hooked up mainly due to WAF, and I also have very limited placement options. My room is 20x 24 x9, and opens into another large area with a vaulted ceiling, so there’s some cubic footage in play. I prefer both subs hooked up, but one sounds better in my situation than none. It’s a treat when I run both subs and pull the speakers out where they sound best. You can buy a decent sub from Dayton or Monoprice for < $200 if you want to experiment before sinking more money into it.

Even low cost subs like the Dayton have variable low pass crossover frequency options, separate gain, and two phase options that help give some options to dial in the bass to suit your needs, even without many placement options. I run mine from the amps into the high level inputs, keep the low pass crossover frequency very low to avoid directionality and resonance issues, and keep the gain very low so it just augments the bass from the mains. I don’t "feature" the sub. It's subtle... I barely hear it except for on heavier bass passages.

I have a KEF KF92 subwoofer in a room similar to yours. I also got their remote transmitter for it so I can locate it where it sounds best, which for me ended up being in the middle of the room, behind the sofa. This has different curve settings for different locations in a room: Corner, wall, room. Good starting points. 

This is my third sub, and I am very happy with it compared to the others. I see that someone recommended the SVS 3000 Micro. I had a pair of them for a short while, then sold them. They didn't go very low in my room and I couldn't get a good setup with them. Though I will say SVS is a good company and the fit and finish of the Micros was excellent.

@jpwarren58 Wrote:

Looking to add a subwoofer to my 2 channel system.

See article below:

Mike

http://www.soundoctor.com/whitepapers/subs.htm

Thanks ditusa...

Very good article that seems to detail and explain well my own bad experience with a SINGLE subs added to my system... I sold it because i was not prepared for this task at all ... :) In the mean time i learned room acoustic and i discovered why connecting a single subs is a bad idea most of the times if done without any help....

Now my headphone goes under 30 hertz i dont need subs...

This article is very good :

«

Understand that the largest percentage of all audio issues is room acoustics. You cannot put a great speaker in a marble shower stall and expect it to sound good - it will sound like a speaker in a marble shower stall. Room acoustics itself is a very complex set of interactions of physics and perception.

Sadly, there are many instances where manufacturers or individuals skew the relevant terms and confuse people. For example, beware of (and be aware of) the dangerous term "Room Tuning". You CANNOT tune a room using an "equalizer". You are tuning THE SOUND SYSTEM with the equalizer - the room is still the same. REAL room tuning means anything from sticking pillows in the corners to rebuilding the room (perhaps correctly) from scratch, incorporating a set of acoustic devices and parameters which sometimes seem nebulous but get a desired result. Because of this nebulosity of all the acoustics terminology (not to mention the international differences in measuring techniques, terminology, and ’scales’, which are substantial) it is often difficult for an end user (and many audio professionals, for that matter) to be able to mentally visualize just what a room without standing waves will sound like, or a room which is so rolled off that the high frequencies seem to "fall to the floor". »

What he wrote is so true, understanding it i rejected the idea of using an electronical equalizer first and instead designed my own room MECHANICAL tuning... First i used passive treatment with a balance between diffusion/reflection/absorption... After I created my audio room with one hundred Helmholtz resonators tuned incrementally on 6 months period around my listening position and the speakers ... I called that : "a mechanical equalizer"... The results were stunning.... No speakers at any price can beat the room...And a good room easily beat most of the times any speakers at any price in a non dedicated room...

By the way half of the issues and problems with headphones are related to the shell acoustic relation with the driver and the acoustic content of the shell or lack of...Something headphone marketing never adress, because to sell a product you dont point to the problems but to false solutions : improved driver with a thinner membrane for example... It is not enough to have a good driver, all my past 9 headphones had good drivers, none had acoustic content and device  in the shell/cup, save one... The only one i like... AKG K340...

I just upgraded from a GoldenEar ForceField 4 to a SVS SB-3000 in my setup.  There is a dramatic difference in depth of soundstage.The only way I can describe it is to say that it is like night and day. One subwoofer can be integrated into your system with a little effort in placement and level settings.  

Just got a Rythmic F12SE has lot of settings here. 12X16 room well treated. No BOOM crap here. It sounds pretty good at their default settings for starters.Fronts are Fritz Carrera Be’s. Amp is a CMII. One question though, use the variable or Fixed outputs on the amp? Using variable now so I can control the Sub volume from the sub mainly. Fills in the lower octave is what I’m after. Any suggestions on this Variable or Fixed. Please. Not placed yet but I hear no foreseeable problems making it good. I don’t have the room for 2.

Dear @jpwarren58  : The main issue could be not if you need one or two subwoofers.

The main issue is that your really good Ryan speakers are a two way design crossing at 2khz and even that maybe you don't know that same woofer/mid-range driver goes down at least to 35hz and : what does that means?.

It means that the speaker has a very high IMD that comes from its bass range notes/harmonics that puts alot of " trash/dust " to that part of mid-range sound. That woofer at the same time that's reproducing 40hz-50hz is reproducing frequencies not only at 2khz but even a little higher, so the woofer excursions goes and degrades the mid-range frequency with that developed high IMD and this is the main issue why you need not one but two subwoofers connected in a way that the Ryan handle all the frequencies over 90hz-100hz and the subs below that frequency crossover. 

In that way the low bass range will be reproduced by drivers designed to handled that critical low bass range ( in an audio home system MUSIC belongs to the bass range, as better this range as better what you are listening. ) and along dedicated amplifiers designed for that bass range. So now your mid-range will shines as never before and the HF too as the bass improved.

Btw, Dirac Live digital process can help you and any one else not only to integrates subs in any system but will improve everything in any home room/system.

Regards and ENJOY THE MUSIC NOT DISTORTIONS,

R.

I'd like to help but I'm confused.  OP is asking for a help pairing a sub to a two channel listening system but lists both KEF R3 AND KEF LS50 as the speakers.  I'm confused.   

I have an SVS Cylindrical Sub that has a small foot print, but vertically it is quite tall for my HT and I have two Hsu subs for my main stereo system. Two smaller subs will give better in room performance than one larger one IMO, but no harm in trying a single first. If you contact Dr. Hsu at Hsu Research and give him your room dimensions (including doorways) he will work with you for best results.

Dual rel subs are a good option for filling in the mid low bass like bass guitars very well. But for the super slam of HT and organ music that you can feel, Earthquake Sound has something called the tactile transducer. When mounted under chair or couch, your bass will no longer be an issue. 5-40hz. 

Budget $2000-3000.

I have multiple speakers that I use to compare and keep things interesting.  

Thanks for all the suggestions.  A complex subject for sure.  

I have 2 SVS subs, smaller room SB3000 and larger primary room SVS SB4000. Smaller sub RCA  hook up and larger balanced. Love them, as they are both operated via Bluetooth for their adjustments. No more getting up and down 400 times to adjust things. Both of mine integrate well, never here them per se, as its supposed to be. Both 2 channel music systems,NOT CHEAP.  Great warranty too. Robert TN

@jpwarren58  : Not complex, it could be complex if you insist in only one subwoofer and do not care about the very high Intermodulation Distortion and Total Harmonic Distortion the Ryan speakers havs.

Subs: HSU or Velodyne.

R.

Suggest you look at B&W’s top line of subs, the DB series. My Magico dealer recommended them. My JL Audio f113 sub craped out so needed a replacement. Bought a pair and they are excellent. Easy and fast to integrate with my Wilsons using their onboard software and your smartphone.

@jpwarren58 , If you try adding just one subwoofer to your current situation you will be very unhappy with the results. I suggest you wait until your circumstances improve. At any rate adding just one sub is never a good idea, Two is the minimum. 

Mijostyn is right for me...

I added ONE sub few years ago, because so good was the Mission Cyrus in the bass  they are not  good up to under 45 hertz and organ music goes under...

I disconnected it the same day and sold it... ( Kreisel k9  sub )

integrating subs is a job of his own...

@jpwarren58 , If you try adding just one subwoofer to your current situation you will be very unhappy with the results. I suggest you wait until your circumstances improve. At any rate adding just one sub is never a good idea, Two is the minimum.

You left out the single BEST brand of subs to consider for two channel: REL. Why? Is a budgetary constraint?