Subwoofer for music, how low?

I am looking for a pair of subs for music. I plan on having four if the two can blend with my speakers.

I have the Tekton Double Impact and tomorrow I will get a set of Buchardt S400Mk2.

I have been looking at the REL T/9x but the only go down to 27Hz at -3db. Should a sub not go down to 20Hz?

I live in Denmark so I have fewer options. I really like the swarm sub array but to costly to get it to Denmark.

I am looking for recommendations. It could be DIY or a specific sub.

I am open for suggestions


Merry Christmas



Very, very little music content is in the 20hz range so I wouldn’t let that be a major factor in sub selection. 27hz is plenty low, and REL is extremely well regarded..

Like everything in life, it comes down to trade offs & compromise. Yes, 20hz has been the mark we have been taught to shoot at. But in reality, very little music goes down to 20hz. Then too, there is the trade off of size. In order to get down lower, you need a bigger box. Plus it costs more. Then there are the specs. Is it rated conservatively or is it rated better by manipulation for sales.

The nice thing about the Rel is how easily it blends and how much bigger it makes your main speakers sound. Plus it uses high ;level input from the speaker terminals on the amp. I have had them for 20 yrs now and was one of my best upgrades.

Merry Christmas to you ! 

I have two REL T9i and love the sound.  They are subwoofers with sound that contradicts their specifications.  

Mine play down to 20Hz in room at the listening position and have more than enough power, punch and impact in my med-large room. 

Of the several other subwoofers I have tried the RELs are the only ones to not color and obscure the midrange and they blend perfectly well. They are so easy to adjust so that they blend with your system- think days instead of months.  

No other subs for me.  Peace.  

The key to your question was music. Everyone chimed in about "most" music hitting 20hz. Some does. Rel is a coupled sub. In other words your floor is the bottom of the slot on that type of sub. The best way to make that type of sub work is, mass load the box and literally glue it to the floor. You will feel THAT type of sub.

The question is, do you want to feel the sub through your bottom (the whole house) or hear and feel the sub in your seated position? NOT through your BUTT or FEET or the plaster falling off the ceiling or the plates rattling in the kitchen, BUT only at your listening position?

If the sub requires coupling to work, you might want to think if that is the type of "BASS" you want. Some love it. The drunker I get, the more I like it, no doubt about it. The only issue is, I quit drinking 40 years ago..:-)


T/9x is terrific sub, I have the T/9i Red Gloss, would love to add a second...I use a pair of S/5 SHO in main system...

DEBRA isn’t very expensive. James R. No idea on the shipping. I thought some of the parts were from Parts Express, like the amps. They have pretty good shipping rates too. Flat packs, there are a few sources, some better than others. PE is one.

How much material does it take to make 4 1cf boxes? Under a 4 x 8 sheet of 3/4" Hardwood, Plywood, HDF or MDF. Chip board will work fine for subs.. They don’t have to be pretty.

You can add a Mohawk to your subs.. :-)

Man secures Guinness World Record for tallest mohawk

Let me hunt up some parts I would and ARE using. 


4 10" 44-10s. This is my personal favorite sub of all time. This will hit what EVER  you want, no problem.


I use Behringer NU12000s and a DCX2696. The DCX has 6 outlets for 6 different setting or you can use a 4 module model like a NU4-6000. So we are clear in 2cf boxes and with a 12" passive radiator they will hit below 20hz direct coupled. Excellent cone control. Super bang for the buck.. 4 will pressure a room VERY easy. Thats 4 active 10" and 4 passive 12". ALL are considered medium to high high excursion drivers, for LOW distortion. I've used them for a long time. 5 years ago they would come up on sale for 99.00. NOW 199.00. Worth every penny. I've never had a failure with that driver..

I use it in my car too.. Impressive, IB in the car though, NO port ot passive.. 

One of the best speakers for columns I've ever used too. 16hz 1000 watts columns under 5% distortion. That's VERY low..

Remember DECOUPLE and build to decouple, Air, springs, pods, BUT decouple.. NO spikes for music, EVER. Spikes are for SNOW.. LOL If you do put any driver pointing down, you have to enclose the slot. You have to add a butt plate. Otherwise it has to be on the side or top (not the best but not bad with a single driver).




Thanks what passive driver are you using. would also like to know more details like cabinet size and driver placement

No, there is no "music" at 20Hz- well not much anyway. However, there definitely is musical content that low, and it makes a huge difference. Mostly it is the lowest ambient resonance of the recording venue. This is the super low frequency throb you feel at a concert hall, but it is there on a lot of other recordings as well.

Very hard if not impossible to accurately reproduce with only one or two subs due to room modes and cancellation, it is easy to do with four in a distributed bass array. The result is bass like you never heard before. Not just bass you notice with music, either. Way better than that. When this ultra-low frequency ambience is accurately recreated it makes the system and room disappear leaving you with a greatly improved sense of envelopment. The music is not spread across the room in front of you any more. You are now in the recording venue.

The beauty of this method is it no longer depends on finding a super powerful sub that goes down low. In fact you can use any four subs, they do not need to match, can be literally anything. Perfectly suited to your situation as you can simply buy whatever 4 subs are readily available in your area. Rely on the fact that using four will outweigh any considerations of what they are.

I have by the way done all the different permutations to know the above is all true. Tried a whole bunch of subs, one at a time. Killed myself moving them around. Tried in vain to get good bass. Cannot be done. Forget about it. When you hear people say they got great bass from one or two, ask if they heard four or five. So how do they know?

I have one Talon Roc powered sub, two sealed 10" and two ported 10" passives run with the same Dayton SA1000 amp Duke uses in his Swarm. Duke helped me building mine. I am returning the favor passing along what I learned. This gives me 5 subs, and I have tried them all kinds of different ways. Killed myself so you don't have to. Just get four, any four, you will see.



This is A passive. I use one that the mass is on the outside. You don't have to remove the driver to add mass. The washers are on the outside and act as a phase plug also. When I get close the mass needed for the tuning I want, I add Mortite (a  soft nonhardning putty) to finly adjust the (Q)uality.  I remove as little as the size of peppercorn at a time. Just as the BOOM goes away you have tuned your sub to your speakers, your room, your cable (type and length) and your amps. THAT is an important little tuning trick isn't it..

Try to find that with ANY sub manufacture anywhere today. The last company to offer that type of mechanical tuning for a sub went out of business in 2012. VMPS. It was a shame. Brian Cheney new BASS like no other.  That is who I learned from. He had subs just like REL at first... THEN he changed in the 90s and decoupled, HE learned. Most of the other manufactures didn't. Now you know why they NEED DSP for your room.

They (most manufactures) don't know HOW to build a friggin' sub without DSP now It's cheaper and easier for everyone. It's NOT the best way it is A way. Look at most REL products, they don't even have that.. Good Boom Boom though. IF you like boom boom.. Nice paint too..:-)


I didn't mention servo bass but it is best for everything. Expensive BUT it is an end all, once and for all bass system.

I used every type of bass system there is, including folded horns for a few years..

The electrical, the room, the bass. One, Two, Three. Foundation UP, NOT the other way around..

You want to know more keep asking questions. I'll dig up some pics or take some, better yet..

It's nice to find someone who likes to learn the right way. NOT a way.. I got a few up my sleeve. 

MC is giving good advise, smoothing the bass, more is better. NOW tune every sub to your room with mechanical (Q)uality..

Any issues after that are a very simple PEQ adjustment.. 56hz, 71hz, 81-2hz (close) 8, 9, and 10 foot ceiling modes'

Happy New Year

This is a CSS type, the mass is on the outside, BUT the passive is not real sensitive, this type you would add or remove large amount of putty at a time to notice a Q difference.. It will work just fine though. This one is good to 7hz is that low enough? LOL


Check out the SVS 3000SB , or SVS 3000 micro depending on your needs and room size. They have a great user adjustable interface on the App which you can download for phone or tablet , the have a 45 day return ,they pay for shipping 

and a 5 year transferrable warranty. The app alone is great  I have the 3000SB-sealed box in true music the grand piano can ho down to around 27 hz which btw is below hearing more vibration low frequency ,30 hz is typically the limits of hearing actual musical tones , the sub can do below 20 hz great fior movies and electronic music ,and settings for movies , and music can be stored settings.

Food for thought:  Kick drum fundamental can be around 50 to 90 hertz.  Bass guitar fundamentals are 40 to 400 hertz.  Lowest note on the piano is 27.5 hertz.  A Roland 808 drum machine kick drum (used extensively in rap music) has fundamentals around 60 hertz. There is a lot of energy in the 50 to 80 hertz area in most recorded pop/rock/country/R&B/Folk, etc., music.

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Still in experimental stage myself, but so far I am with oldhvymec, a decoupled, dual opposite firing box equivalent to two subs. Yeah, I too thought not much signal in Octave 0. Well, there's PLENTY down there; you control "boom" with SVS decoupling feet and lowering sub gain since a whisper is all you need. Main benefit is opening the mid on the towers. My own remaining problem is how to integrate two ambient subs in a difficult room. I'm trusting MC's advice that the key is not what, but where. Thx to OP for keeping this ball in play.

Walk around outside and look at a Real Time Analyzer graph on yer phone...everybody has one of those, right? Note the frequency range of the normal world...go ahead...I'll wait here. See that? In any case, subs (or the rare "full range" speakers) add the bit of "life" generally missing from playback without lower frequencies. 

I use two REL S-812's in my stereo set up.  I have the crossover between 20/30 HZ and sit them right next to my Wilson Alexia speakers.  Did I NEED sub's? Absolutely not....however, they have added so much depth and soundstage to my system that I will always have subs no matter what type of speakers I own.  Goal is to have an array of 3 on each side (6 total) to further enhance the "live" experience.

Is it aiming to low if I buy for SVS SB1000? There are on sale. Or I could pay some more and buy the new SVS SB 1000 PRO

@erik_squires 100! Most def easier said than done! A month later and I’m still trying to fine tune a T9X into my room. My previous sub was a T-zero mkiii that was pretty much plug and play. This 9X is a different animal.

@martin-andersen Also look at the 3000 micro. I just put two of these in a small system with KEF LS50W2’s and they are pretty awesome for the money.

Any sub is better than none and two are better than one. Get what you can afford and enjoy!

+1 for REL.  Start with one and see where it takes you.  Too many here trying to persuade you to join their swarm club without knowing what one good sub will do in your specific listening room.


I've been wondering if my Main tower speaker with built in powered subs plus my two SVS Ultra 13 subs with upgraded plate amps (more watts and DSP app) will perform like a swarm configuration l love adjusting my subs on the fly from my listening chair I have the SVS isolation feet on my subs and they really help stopping my pictures from rattling off the walls

Yes, that setup should do it. If your bass sounds balanced and natural, you're done. If it sounds slow and overloaded, try moving the stand-alone subs to different parts of the room until it sounds right. You can excite room "modes" if a sub is in the wrong location.

I'm also using the SVS isolation feet on my JBL subs and they really work.  My pictures have stopped rattling and dropping to the floor.

Is it aiming to low if I buy for SVS SB1000? There are on sale. Or I could pay some more and buy the new SVS SB 1000 PRO


I believe SVS offers a trial period and a great deal more control options.

The T/9x’s manufacture rating is actually -6db @ 27Hz. Like the many who’ve never experienced a high performance subwoofer that plays equally well with both music and film, have high praise for their products. Every REL sub I’ve auditioned in my home has never come close the manufacturers frequency specifications on their own. They call them "Sub Bass" speakers, or they used to. Good luck with it.

if you go SVS then def the Pro version.

remote adjustments are key to good integration 

i have two svs 1000 pro and apps use REW software and

microphone to help with positioning and eq etc.

@martin-andersen --


I have been looking at the REL T/9x but the only go down to 27Hz at -3db. Should a sub not go down to 20Hz?

I live in Denmark so I have fewer options. I really like the swarm sub array but to costly to get it to Denmark.

I am looking for recommendations. It could be DIY or a specific sub.

I am open for suggestions"

Re: swarm sub array (or DBA), any sub brand and size in a quartet will do. Some may feel otherwise, but I would stick to 4 similar subs should you go this route. Moreover, from my POW: have them placed symmetrically, like 2 of them flanking the mains in their respective corner, and the other 2 placed symmetrically in the corners behind you. This way you can also maintain a left and right field and couple them in stereo if crossed above 60-70Hz (and should you decide to high-pass your mains). I know, to some there’s a rigid 80Hz barrier below which bass supposedly isn’t directional, but I disagree with such hard cut stances.

I would like to make a comparison with horns. Horns used from the upper bass/lower midrange on up can be small(er) or rather large covering more or less the same frequency span, the main difference being that the larger horn is able to maintain directivity control lower in frequency compared to the smaller ditto. This is vital for a number of reasons. Predominantly smaller horns are used in the domestic realm simply because smaller size equals better sales, and very generally speaking the smaller horn variant will sound as if focusing the energy of sound in a more concentrated fashion vs. a bigger horn covering the same frequency range. This concentrated characteristic of the smaller horn is not without merit and can have its own lively quality in a sense, but when you hear the bigger horn here (which is usually much bigger) there’s a more relaxed, room filling and physical presence or sphere of sound even. Which is to say: to my ears, all things being more or less equal, the bigger horn will sound less like a horn, or just less reproduced overall, and not unlike very large (and very dynamic) panel speakers.

Moving our attention to subwoofers there are things at play not wholly unlike above horn example; the bigger and more efficient the subs, the less they sound like subs. What does a ’sub’ even sound like, typically? Like something that would call attention to itself as a separate entity. For some reason I’ve never been able to integrate smaller cube-sized, lower efficiency subs in a satisfying manner with the mains: they always end up drawing some kind of attention to themselves, less pronounced though when set up as a DBA.

Using big, efficient subs on the other hand is generally a different matter. They’re not impervious to or unaffected by bad implementation, but properly set up they blend in and fill the room more effortlessly and smoothly while usually having less lag. Bass just happens in the listening space, not least via horn-loaded principles, and once you get used to that there’s really no turning back to them small cubes.

So, if you choose to go with the smaller cube-sized and less efficient sub solution I’d recommend you don’t skimp on driver size, and use at least two of them. Should you go with 4 subs for a DBA - indeed, in any case - set them up symmetrically. Consider high-passing the mains as well to relieve them of LF.

If you want to try out big, efficient subs, start out with a pair placed symmetrically to the mains. If you’re not afraid to venture into DIY consider the Cinema F20 front loaded horn sub by "lilmike" (Google them), or his slightly smaller PicoWrecker tapped horn. Both will reach down to honest ~20Hz, but be aware they’re not small (the F20 takes up 20 cubic feet per cab). Add a MiniDSP and a pro power amp, and you’re good to go.

+1 for distributed bass array

If going Tekton, might as well get a couple (or 4) 2-10 subs from Tekton and yep those do go down to 20hz - which is an important thing for a sub to do in my book.

Virtually no music is down in the 20-40 hz range and I doubt the t9 can really deliver there anyway. I have a REL S5/SHO and properly set up in an acoustically tight 13x 22 listening room it does a great job of delivering deep bass- when I measured there just isn't much music at those very deep levels. Most sub activity is in the 40-70 HZ rang or so. I'd go with a larger box and drivers which will provide deeper and louder bass than the T9. 

I have a Totem Thunder, with my Forests but just ordered a pair of SVS sb-1000 pro subs. I’m not in need of excessive bass, especially with the Forests that have a considerable amount of bass already. I wanted a matching pair to give flexibility in my small/medium size room. They have a sale going on right now, so I went with the pro series as it has an app for my phone that can control the many features of them. Nice to be able to control them without trying to “access” the controls.

If you can afford JL Audio, I would go with them. I’m utilizing mine with the Wilson Audio speakers and the Wilson Crossover. Easy to blend in the room and you don’t get wasted sloppy bass. It is very precise and accurate down to 20hz if any of your listing music goes that low. One of the best subwoofers around and a great reputation too boot.

Maybe I missed, but didn't see the size of your audio room. With base, the size and shape of room, along with budget, will determine what to do - one good sub or a swarm of subs. 

I have a medium/large room (14' x 27'' open to an additional 11'x13' adjoining room) and a single ADS Sub loads the room from 60Hz down to 20Hz incredibly well. In general, the smaller the room the more need of multiple subs to load the room with convincingly deep base. 

If your room is a bit smaller - say 12'x20' (3.5m x 6.5m) for deep full base I would think you could do very well with a pair of good subs that will go down to 20 or 23 Hz (you might check the used market) and set them to operate below 60Hz.

Keep in mind, quick and punchy base is not deep base. Quick and punchy base (at and above 60Hz) and deep base, getting down near 20Hz, should integrate and augment each other and even after getting the right subs - that will take some time, work and patience.

Best of luck......Jim

Denmark? Did you say Denmark? The country of ScanSpeak? Their 'Revelator' series is wonderful for DIY.

Add Bryston for amplification and you have it all, except DSP, which can be obtained from an audio processor (digital doesn't matter for low frequencies). Bryston has a factory-refurbish program for older units, and they come with a 5 year guarantee. SST series is older but plenty good.

Good luck!



Thanks for the feedback!! I have learnt a lot and would like to thank you all and wish you a happy new year.


I would especially like to thank millercarbon, oldhvymec and physics for their out of the box approach to solving the bass problem.


My takeaways

  • Room, Power, Bass could not agree more
  • A sub should not excite the floor. So no T9 to me.
  • Servo is good
  • 4 subs are needed to address room modes. Especially in small rooms 


This is what I wrote to Rytmik Audio



To Rythmik Audio


I am looking for a solution for uneven bass in my room.


The room is 26m2 and the walls are thin plasterboard. Wood floor with concrete half a meter under the floor. Ceiling goes from 2.3 to 3.8m


I have been looking at getting a bass array like the SWARM but think servo sealed subs is the way to go.


This is what I hope I can get from buying 4 F12G

  • A sub array using MiniDSP 2x4 HD. This will be a mono array.
  • Ability to try only two in a stereo setup using high input like on REL.
  • I hope it will be possible to use the plate amps and the drivers to build a GR research dipole sub.
  • I would also like to add the subs to my HT system. So a separate connection to HT and music. Is that possible?


As you can see my hope is that I should newer need any other bass solution than I can get from buying four of your subs.


Please correct and enlighten me. I have newer owned a sub.


I live in Denmark and hope we can find a better price for transportation. I will have to pay 33% on top of the total invoice. That's right also tax on transportation.

A subwoofer that meets all your criteria has a new home in Germany. Audio Reference purchased California based Velodyne Acoustics. Now marketing some new models and assembling a world wide sales and service network.

While it may be more than you’ve considered for your budget The Velodyne Digital Drive Plus can serve as an incomparable master control for less expensive slave subs in an array. The Plus has the ability to control a daisy chained system of units regardless of their inputs. The Plus offers one of, if not the most uniquely easy to use and remotely controlled, subwoofer dedicated Room Optimization / Equalization programs.

After Auto EQ has completed, on pages 10 and 11 of the DD Plus Interface Manual describes how to use the Frequency Response and Parameters Screen. This is a simple drag and drop control of multiple parameters that are visually and audibly made at the listening position to closely match or augment your main speakers basic presentation from 200Hz on down.

Compare the flexibility the rear panel offers to other subwoofer panels in the User’s Manual below

I assembled a four sub asymmetrical array in my largest 26’x 35’ room and they did eliminate ALL the rooms modes. I later settled on two asymmetrically located slaved Plus’ which allowed a noticeable mode in an unused corner of the room. The room loading and intensity has been easily maintained with just two subs ever since. Point being you may not require as many subs as you may think you do. What ever you decide on take it slow but keep it low.

FWIW, ["Virtually no music is down in the 20-40 Hz range"]?

Whether my Bass playing skills would be deemed musical is certainly subjective. Depending on my tuning and without the OctaBass on my Lakland’s stainless low B rings significantly at 31Hz which most 10" subs can easily output. Those B and E strings are bread and butter for a Bassist.

Contrary to what has been said to the OP on the topic of implementing a distributed bass array (Swarm), the positioning of four subs should not be symmetrical, but asymmetrical.

Symmetrical positioning of subs only increases the chance that room modes will be accentuated instead of reduced. Asymmetrical positioning increases the number of first reflection points, which should result in a smoother overall low frequency dispersion.

+1 distributed bass system. Tried everything else for 20 years and adding one 10" sub towards the rear of the room solved the problem of weak sounding bass. I have 3 now and want a 4th for more power and headroom, smoother response, and trying stereo with 2+2.

+1 remote control to make tuning easier. My 10" is paradigm and the iphone app really makes it easy to dial in.

Dear @martin-andersen : First than all you don’t need 4 subs to have a fine room/system with out standing waves at your seat position. You need only two powered subs with a high pass filter for your main speakers.

I respect what other gentlemans posted about but all them are wrong. I repeat that for one seat position we need tewo powered subs and that’s enough.


Now, yes you need that subs goes below 20hz. Again who tells/tolds you other thing just does not know for sure what’s talking about.


One critical issue is that we need not only that subs goes below 20hz but we need too a high quality level of that bass range performance. Not all subs can do that.


My advise to you is to look at Velodyne and HSU. As an example the THD on the Velodyne subs are below 0.5%. No other of the subs named in this thread are nearer that critical figure.


I own an out of production model that with its patented accelerometer servo control check over 16K times each second the woofer movements to preclude distortion levels go higher thaN 0.5%.




Look first than all for bass quality and not for the : boom, boom, boom that is not MUSIC at all


Regards and enjoy the MUSIC NOT DISTORTIONS,


Sounds like you got it figured out. Servo or sealed, powered or ported, get whatever you like just get 4 and you will be fine. Then if you also are able to budget for Townshend Pods under those subs, and Podiums under your speakers, this will greatly reduce room resonance even more while giving a large improvement in clarity, detail, and 3D imaging. The combination of DBA with Pods gives a feeling of envelopment, of being in the recording venue not merely having it in front of you. 

A big reason for this is speakers and subs put a lot of energy directly into the room. Being coupled to the floor vibrations excite the floor and walls. The whole room physically resonates. Isolating speakers greatly reduces this. You have to hear it to believe it. Like adding a pile of tube traps but without the wasted space and with improvement in detail you just can't get any other way.

If you need to save money you can get a good share of this with spring isolation like Nobsound springs. These are not nearly as good as Pods but a lot better than you would think for how cheap hey are. Of course they can be used in combination. Speakers on Podiums, subs on Nobsound is a good compromise if you need to save money.

With DBA you will be amazed how easy it is. Set them different distances from corners (asymmetrical), set crossover below 80, set levels, and you can tweak it from there but already it will be very, very good! 

Based on a rectangular room, with multiple seating this is what Todd Welti’s research showed (I assume his research was more geared towards home theatre application). Google Todd Welti if you’re not familiar with him.


"It can be seen that there is less difference between “good” and “bad” seats, and that there is less low frequency support for some configurations compared to when the grid is centered and unweighted. Two and four subwoofers at the wall midpoints are still the best configurations overall. Four subwoofers in the corners does not seem as advantageous as when the grid was centered. There is still little or no advantage to using a large number of subwoofers. LF factor still goes down for higher numbers of subwoofers."

"CONCLUSIONS • How many subwoofers are enough?

Four subwoofers are enough to get the best results of any configuration the best results of any configuration tried. Two subwoofers is very nearly tried. Two subwoofers is very nearly as good and has very good low as good and has very good low frequency support as well."

In other words, you may be wasting your money having more than 2 subs, and certainly wasting money with more than 4. The best outcome is between 2-4 subs, but you need measurements to determine which is best. Is it worth spending money to fix a 2-3dB dip/peak in your room by adding a 3rd or 4th sub?

I think you’re better off starting with 2 subs (especially if your listening environment is single sitting for music), spend $100 on a good mic and some cables. Take some measurement using REW (free software) to see if more subs are required. You could save yourself a couple of thousand dollars.