Looking to upgrade my sub - recommendations?

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I currently have a Polk PSW10, together with a set of M-Audio AV40s. I also have a set of Audio Technica Pro700mk2 headphones.

I'd like to upgrade the sub. I generally like the PSW10, but I listen to music with huge bass, and the PSW10 doesn't go lower than 35hz. So, I would like to get something that goes a little bit lower, maybe to 25hz or so. My hearing is not the best (used to live near an airforce base), so the sub's ability to actually produce lower frequencies is more important than its clarity.

The problem is, I will be using the sub in a small room, and have little space. Are there any subwoofers with a smaller cabinet size and decent price? I would like to not spend more on my sub than my speakers and headphones combined.
 
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Here is my recommendation for the best sound quality:
A Rhythmik Audio servo subwoofer. 12"

http://www.rythmikaudio.com/

"Direct Servo uses a very thin sensing coil which is wound adjacent to the voice coil. The coil acts as a custom made microphone which creates a signal which is then used to correct any difference from the original signal. Any non linearities are instantly corrected."

Do some google searches on direct servo subwoofers.
 
Thanks everybody for the recommendations.

I have a few questions:

1) Can a sub smaller than 12" actually get down to 25hz? When I made my OP, what I had in mind was a 12" sub specifically made for small cabinet volume (like some car stereo subs are, such as this one). Should I consider smaller ones?

2) Is impossible to get a sub that can get down to 25hz for less than $250? I could get one of the ones recommended, but it doesn't seem logical to pair a $120 pair of speakers with a sub priced at twice as much. This is especially the case since pure sound quality is of less concern to me than the ability to actually hit the low frequencies. If I truly need to spend more, please let me know. Might upgrade my whole setup.
 
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Can a sub smaller than 12'' get down to 25hz? Yes.

http://www.svsound.com/subwoofers/ported-box/PB-1000#.U4W7oPldXEk

The woofer is 10'' and gets down to 19hz at a +/-3db rating, which is damn good.

It's possible to get a sub that goes to 25hz (at some lower db level) for around $250 (Polk PSW505, BIC F12, etc), but getting one smaller than 12 inches might pose an issue.

Edit: SVS even allows you to upgrade your sub (with full credit for you previous sub, except shipping, going towards the new one) within a year if it's in good condition with original boxing.
 
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1) Can a sub smaller than 12" actually get down to 25hz?

The HSU can easily hit that especially in a small room. The SVS more so.

2) Is impossible to get a sub that can get down to 25hz for less than $250?

I doubt you would find a sub with any usable extension at 25hz for 250$. If you want want lots of bass the SVS PB-1000 is probably your cheapest option. It will go lower and louder than the HSU but also costs more. THe HSU is your best compromise for price/performance.

Get the sub you want and if you dont think it pairs well with the M-Audios look to upgrade them later.

I have owned HSU and SVS and they are exceptional subs for the money
 
As others said it is basically:

1) Yes
2) No

:). With subs, as with many things, you have to pay more to get more. The lower the extension, higher the levels out of a small box, the more it'll cost you. Just the realities of engineering. Also with subs bigger is better given that they are dealing with very large waves (bass waves can easily be 40 feet long).

So for low and loud they can be expensive beasties, and large ones.

Something you can do to increase your bass is exploit room gain by placing the sub in a corner. Tuck it right up near the walls. That hurts sound quality to an extent, in that there's less linearity in frequency response and perhaps some more distortion, but it increases bass levels, particularly low bass.

Subs actually can have a response LOWER than stated in a room, when room gain is taken in to account.
 
There is no replacement for displacement. You must go with a big subwoofer to get significant performance at low frequencies. Room placement also matters. The best 10" subwoofer in the world would make an average (or worse) 15" subwoofer. It is more efficient to radiate sound via area than it is via excursion, and the technologies (such as XBL^2) that enable high excursion require looser tolerances in the gap that translates to significantly lowered efficiency. Bigger is better; buy the largest subwoofer you can afford/fit (of the good brands). That's not to say that all large subwoofers are better than all smaller subwoofers, as large subwoofers can be made poorly/cheaply just as much as anything else can.

SVS, HSU and Rhythmik are all solid choices for brand.

Personally I built my own with an Acoustic Elegance driver, and I will take Acoustic Elegance subwoofers over any other subwoofer on the planet, personally.
 
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I doubt you would find a sub with any usable extension at 25hz for 250$.

Yep, that's the problem. The subs may reach 25hz, but it'll be at a significantly lower db level. Getting a small sub to audibly put out those frequencies is going to cost.
 
There is no replacement for displacement. You must go with a big subwoofer to get significant performance at low frequencies. Room placement also matters. The best 10" subwoofer in the world would make an average (or worse) 15" subwoofer. It is more efficient to radiate sound via area than it is via excursion, and the technologies (such as XBL^2) that enable high excursion require looser tolerances in the gap that translates to significantly lowered efficiency. Bigger is better; buy the largest subwoofer you can afford (of the good brands). That's not to say that all large subwoofers are better than all smaller subwoofers, as large subwoofers can be made poorly/cheaply just as much as anything else can.

SVS, HSU and Rhythmik are all solid choices for brand.

Personally I built my own with an Acoustic Elegance driver, and I will take Acoustic Elegance subwoofers over any other subwoofer on the planet, personally.

That makes sense. It seems I'm not going to find a sub with a compact cabinet for the price, especially as some of the 8", 10" recommendations listed also have pretty large cabinets, fairly close in size to this 12" sub, which is on the Amazon most popular list.

So, ignoring cabinet size, what would you guys recommend?

I would spend the money on better speakers first.

Why? My hearing isn't as good as most, so I will not be able to tell the difference.
 
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So, ignoring cabinet size, what would you guys recommend?

Just driver size? 12-13" works fine. Most of the best consumer subs are in that range. There are larger ones, but it is generally not needed/useful in smaller rooms.

In terms of cabinet size it depends on what you want. Bigger is better basically, but you can have small ones that are acoustic suspension designs. They just cost more to achieve a given level of output/extension and cannot go as loud/low overall as larger ones.

If you can swing it, I'm a huge SVS fanboy and they do make smaller subs in the form of their SB-1000 and SB-2000. Their PB/PC subs are MASSIVE though, like you didn't think a sub could be this big kind of massive. HSU is another good choice, as previously mentioned. If you need something cheaper, JBL is a place to look. Their stiff isn't too large and the prices are reasonable (though not budget) and their sound is decent.
 
If you want to play into very low frequency an acoustic suspension design is tricky, unless you want to use a Linkwitz Transform filter and run a LOT more power to a subwoofer that is going to need a lot of excursion (XBL^2). 25Hz might be doable with the right driver as it's not THAT bad compared to 20Hz or lower and since you might not want super loud overall volumes.

It would be easier with a ported ("bass reflex") design. But the problem is that ported woofers have to be tuned to a specific frequency which affects the response curve, and you must cut out all the stuff below the port tuning frequency (well, near it, anyway - you can often go below it by something like 10%) because the driver suspension unloads and the cone then just flails about wildly and can be damaged (as can the voice coil). Many commercial brands will claim that a subwoofer plays much lower than it really does - many will use the F6 or even F10 points (points in frequency response that are -6dB and -10dB in response level) instead of the usual F3 points, which makes the readings seem better. Most will tune their ported speakers up pretty high at something like 35-45Hz to get a stronger mid-bass - usually at the cost of sound quality, but allowing for higher output at higher frequencies that satisfies most people.

So if you do buy a ported speaker it matters more which one it is. If they are tuned higher than you want, you might be SOL. You could extend the port yourself, but there should be electronics controlling the highpass/"subsonic" filter that you may not be able to disable (it would cause more warranty returns if you let ignorant consumers turn it off). If you can disable it (or much better - lower it), the port could just be extended/replaced. You might be able to try extending the port of your current sub - or even stuff a sock in to turn it into a very restrictive aperiodic vent which would be close enough to an acoustic suspension design.

Actually, technically it's not always an acoustic suspension design just if it's sealed... A lot of subs will have very stiff suspension and won't really qualify.... Not that the distinction really matters. Some stuff, especially pro audio, will have soft suspensions for increased efficiency. Those tend to be more woofers than subwoofers though. HT subs are better for LF.

Personally I'd recommend DIYing a subwoofer when your intention is good low frequency response. Especially when you aren't looking to spend $600+. How's the idea sound? You don't necessarily need to cut the box; there are a few options. Not to say that you need to DIY, but be careful when buying the commercial products when looking for real LF. Most of the cheaper products just don't do it.
 
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I agree that you will achieve better performance with a vented design. I prefer the passive radiator variety, but that adds more to the cost. There will be some "room gain" - but it's not entirely predictable and the position of the subwoofer will have a large effect as well: http://www.data-bass.com/data?page=content&id=80

http://www.data-bass.com/data?page=content&id=82 - a good article on the performance differences between enclosure types. If you go through enough of the data-bass database (heh), you may notice that the difference between vented and sealed is often greater than shown in this article's example case.

For DIY:

You linked the Dayton Reference 12" HO. It's a good woofer, and it does work better than the HF in small boxes, but the Fs is too high for what you want.

I actually don't know which of these woofers would give you the size / efficiency you desire, so you'd have to do some modeling work:

TC Sounds Epic 12" (modern TC2+ motor, I think), Dayton Ultimax (it's newer, I'm not 100% sure it's good, but I assume so), Dayton Reference HF 12". The 1st two have large Xmax. You're looking at a large box either way.

I haven't done the modeling work for these woofers yet, so I'm not sure what is possible as far as enclosure design. But you will learn a lot just playing with some of the Theile / Small modeling software.

Unibox (uses excel)
WinISD (old, but still usable)
Bassbox 6 (paid... but a little easier to use)

Input the parameters and let the software plot the predicted frequency response, power-handling vs excursion, group delay, etc. You can then see what kind of box-size you can get away with. Do not just use the PartsExpress sealed boxes w/o quickly modeling the frequency response first. It really does take just a few minutes per driver once you figure it out (and then much longer for you to decide on a box size / tuning)

Problem: Those M-Audio AV-40's may be a bit small to pair with a high SPL sub. You may want to upgrade those later just to match SPL at the midbass to bass transition.
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Pre-Built Subwoofers:

http://www.data-bass.com/data?page=system&id=47&mset=45 - here are some measurements of one of the BIC subwoofers. It'll give you extension down to 25hz just barely. Below 35hz the distortion is evident. [Click the multi-series chart for distortion plots - for bass, below about 10% THD may be acceptable]

You can see, however, that the subwoofer becomes unstable as hell just below 30hz. A real Home-Theater subwoofer in a vented enclosure should probably be tuned closer to 20hz if possible.

So... a budget sub can deliver what you're asking. That BIC one may not be the best option.

The recommendations in this thread are probably better. The HSU STF-2 looks good (VTF-2 for the next step up) and claims to be able to reproduce 25Hz bass despite the 10" woofer. I always thought HSU was decent in-person. My Uncle has used them for...maybe 2 decades...
The SVS pb-1000 (free shipping, but $500) looks good and makes similar claims about its frequency response.

I just don't have in-depth 3rd party measurements on these, BUT: http://www.audioholics.com/how-to-shop/500-subwoofer-roundup - this review indicates that the SVS offers a bit more output below 25hz, and that the STF-2 is no slouch either.

I do think I'd go for a pre-built budget sub in your case. I'm also thinking that the [H] came through with some solid recommendations. :)
 
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The problem with vented designs is he expressed the wish for a small sub. All the good small subs I know of are sealed. You just need a certain amount of space to do a port right.

Don't get me wrong, a bigass ported sub is what I most recommend. Anyone who says "I want the best bass, no other considerations," I'll point them to SVS's PC/PB subs. 2x PC-13s will rock your world and they have the biggest ports you've ever seen (and there's multiple ones so you can tune the bass roll off). However they are the size of small hot water heaters, so I don't recommend them to many folks :D.
 
Archmage: Peerless XXLS is a good choice for the LF... TC Sounds drivers often don't go as low, especially the LMS stuff (which is not the Epic - I think the Epic might be better for LF than the LMS-R or even the Ultra/5400 though)... A lot of XBL^2 stuff will work though those, as I said before, can have lower efficiency due to the high-excursion design.
 
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There are some good small subs that will get under 30 Hz, but they will cost more than $250. The Velodyne Optimum-8 and the Sunfire HRS-8 are a couple. You might could get one used for $250, but not new.

I was able to get a new Optimum-8 on eBay for $500, but they usually go for $700 or more.

Audioengine has a small sub for $350, and if you look around you should be able to find a coupon for 10% or 20% off when you buy direct. It won't be as good as the Velodyne or Sunfire, but still should be decent.

The Audioengine sub is rated down to 27Hz (+/-1.5dB), but won't get as much room boost below that because it is ported.

The Velodyne is rated down to 26Hz (+/-3dB), has a nice flat frequency response, and being a sealed design will get decent room boost below 26Hz.

The Sunfire is rated down to 22Hz (no +/- given) and sealed, so decent room boost. Downside is it's max crossover frequency is 100Hz which is a bit too low for some small speakers.

I have no complaints with my Optimum-8. And it certainly gets lower than any ported sub rated down to 30-40Hz. I have used it with a fairly wide range of speakers from the little $200 Audioengine2 to the $1600 Snell CR7.
 
A Vented design typically has better performance, but I would recommend a sealed design to save space. Vented designs require a much larger box than sealed.
 
A Vented design typically has better performance, but I would recommend a sealed design to save space. Vented designs require a much larger box than sealed.

Meh, Sunfire, klipsch, energy, etc all make small footprint ported subs. It's just that price point isn't cheap. Sealed subs are also a matter of taste... To me they act more like mid bass than an actual subwoofer.
 
A Vented design typically has better performance, but I would recommend a sealed design to save space. Vented designs require a much larger box than sealed.

Better performance as in more volume? Sealed isn't necessarily for space but also performance as in even response, no? Also I think venting helps with cooling the voice coil which is an issue people don't think about a lot, perhaps. Sealed with vented cone! I don't know much about speaker design but I'm really impressed with my new 8" sub that employs this old trick.

Meh, Sunfire, klipsch, energy, etc all make small footprint ported subs. It's just that price point isn't cheap. Sealed subs are also a matter of taste... To me they act more like mid bass than an actual subwoofer.

Oh so definitely not always the case, but often. Good engineering can make 8s pretty thundering, and not everyone has much use for ~25hz waves in their walls. Loudest SQ subs I've ever heard were JL 8s in a large tuned box built by JL themselves. Was absolutely shockingly loud and just rattling your spine up and down the entire fretboard of Les Claypool's bass, with Herb Alexander's kickdrum pumping the air in and out of your lungs for you. (Primus)
 
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Better performance as in more volume? Sealed isn't necessarily for space but also performance as in even response, no? Also I think venting helps with cooling the voice coil which is an issue people don't think about a lot, perhaps. Sealed with vented cone! I don't know much about speaker design but I'm really impressed with my new 8" sub that employs this old trick.



Oh so definitely not always the case, but often. Good engineering can make 8s pretty thundering, and not everyone has much use for ~25hz waves in their walls. Loudest SQ subs I've ever heard were JL 8s in a large tuned box built by JL themselves. Was absolutely shockingly loud and just rattling your spine up and down the entire fretboard of Les Claypool's bass, with Herb Alexander's kickdrum pumping the air in and out of your lungs for you. (Primus)

Sealed will play down lower, technically, but will roll off sooner. It's harder to achieve great low-frequency performance with sealed. You can usually get decent performance. If you use the right driver and are okay with a relatively low efficiency, you can get it to play down pretty low. And you can get it to play very low with tricks like Linkwitz Transform but you REALLY have to watch your power handling and excursion as it's easy to go too far.

Ported is typically a few decibels more sensitive (sensitivity and efficiency in this sense aren't the same, but are directly correlated) but has to be tuned correctly and as I said before you need a highpass filter to cut out frequencies under the tuning frequency. And yeah, the box sizes required are usually 50-100% higher than sealed (and can be even higher the lower you want the tune - but if you aren't tuning for something REALLY low like 16Hz it won't be that bad)
 
So I did some of the box-modeling for 12" subs and... yea the box requirements are just too large for the ones I suggested unless you go sealed (which could work): http://www.parts-express.com/dayton-audio-12-ultimax-subwoofer-and-cabinet-package--300-7096 - That's still large... but probably pretty good. The dayton HF might also work sealed, as well as the low Fs version of the dayton HO (which may even work ported, but has a high moving mass and low efficiency).

The Peerless XXLS 12" that DandragonRage suggested actually has a slightly smaller ported box size requirement, but still larger than that sealed Ultimax 12 above.

The XXLS is expensive and doesn't handle much power, but it still has 12.5mm xmax and low distortion. Furthermore, Peerless has a fairly good driver manufacturing consistency, which is important unless one can measure the T/S parameters.

This is something I neglected. I would suggest measuring the T/S parameters of individual drivers before proceeding to build any vented design. $100 will get you the Dayton Woofer Tester: http://www.parts-express.com/dayton-audio-dats-dayton-audio-test-system--390-806 - but that may be a deal breaker.

SVS actually used Peerless XLS-derived drivers for some of their higher-end subs. Not sure if that's still the case.

If we move down to 10" woofers... maybe the box size will be more comparable to the HSU / SVS 10" designs.

http://www.parts-express.com/dayton-audio-um10-22-10-ultimax-dvc-subwoofer-2-ohms-per-coil--295-510 - Partsexpress claims an F3 of 23hz with a long slot port (more difficult construction) using 1.75ft^3. The max vent velocity will be a bit high, but it's in the ballpark. It has a low sensitivity though - so it'll need more power.

The TC Sounds Epic 10" does not give as good an F3 point. That's too bad; I really like the TC2+ motor. It doesn't strain as much as the XXLS at high SPL.

The HSU and SVS solutions are good, and their designs, I assume, have been optimized. Less headache.
 
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Ported speakers on average are maybe 3dB more efficient than seal box speakers.

But when talking low frequency extension with subwoofers, sealed box subs have and advantage over ported box subs.

For example if you take a sealed box subwoofer with a -3dB point of 30Hz, then it will have a -10dB point around 20Hz. Which is still noticeable output. To get the same -10dB at 20Hz with a ported subwoofer, it would need a -3dB point of around 25Hz.

Also, when a frequency response is listed, but no +/- given, then is it usually using the -10dB points. For example the frequency response for the Polk PSW10 is given as 35Hz - 200Hz, but the -3dB points are listed as 40Hz and 160Hz. -10dB of 35Hz and -3dB of 40Hz is not all that great.

The other subwoofer the OP links is the BIC America F12 with a frequency response listed as 25Hz - 200Hz (likely -10dB which means -3dB around 28Hz-30Hz). So it should get a bit lower and play a bit louder than the Polk.

But I think the OP should also consider the Audioengine S8. It is much smaller (11.25 inch cube), -1.5dB point of 27Hz (so -10dB of like 22Hz-23Hz). It won't play as loud as the BIC, but should be more than enough for the M-Audio AV40s. And it should actually have a bit lower frequency extension. (Search the web for audioengine coupon for discount when buying direct.)

Yet another option is to go on eBay and search 'pinnacle subwoofer'. Pinnacle makes several small subwoofers, and some such as the subcompact 6 or the subcompact 8 often go for quite cheap even for new ones. They are small with -3dB points below 30Hz. They likely won't play super loud but are likely good enough for the M-Audio AV40s.
 
Still love my SVS PB12-Ultra/2 which I picked up a little over 9 years ago - huge dual 12" drivers in a ported enclosure. Easily goes down to 16Hz. Cost an arm and a leg (close to $2k shipped,weighs in at 190lbs) but like others here have stated, a quality sub that will go low will cost you. Especially if you want a small one but don't want to sacrifice performance - there is a point of diminishing return though when you get too small and physics simply won't let you produce what you want anymore, no matter the quality of the components.
 
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Sunfire has a reputation for making compact subs that have tremendous output. I demo'd an SDS12 (their lowest end 12" model) that managed CEA 2010 results of Low bass (40-63 Hz) average: 119.4 dB. It's Ultra-low bass (20-31.5 Hz) averaged a substantially weaker 88.1 dB, though.

A good 'punch' sub, and I imagine Sunfire's higher end stuff is better still, but I swapped it for an SVS and was happier.
 
Search and read the threads at AVS about subwoofers and DIY subwoofers. That will give you tons of information.

I am building two Dayton HO 18's in 4cuft sealed enclosures. They are not terribly big IMO, but I have space for them. My wife thinks they are crazy big, but then again they are 18 inch drivers :)
 
Ported speakers on average are maybe 3dB more efficient than seal box speakers.

But when talking low frequency extension with subwoofers, sealed box subs have and advantage over ported box subs.

For example if you take a sealed box subwoofer with a -3dB point of 30Hz, then it will have a -10dB point around 20Hz. Which is still noticeable output. To get the same -10dB at 20Hz with a ported subwoofer, it would need a -3dB point of around 25Hz.

Also, when a frequency response is listed, but no +/- given, then is it usually using the -10dB points. For example the frequency response for the Polk PSW10 is given as 35Hz - 200Hz, but the -3dB points are listed as 40Hz and 160Hz. -10dB of 35Hz and -3dB of 40Hz is not all that great.

The other subwoofer the OP links is the BIC America F12 with a frequency response listed as 25Hz - 200Hz (likely -10dB which means -3dB around 28Hz-30Hz). So it should get a bit lower and play a bit louder than the Polk.

But I think the OP should also consider the Audioengine S8. It is much smaller (11.25 inch cube), -1.5dB point of 27Hz (so -10dB of like 22Hz-23Hz). It won't play as loud as the BIC, but should be more than enough for the M-Audio AV40s. And it should actually have a bit lower frequency extension. (Search the web for audioengine coupon for discount when buying direct.)

Yet another option is to go on eBay and search 'pinnacle subwoofer'. Pinnacle makes several small subwoofers, and some such as the subcompact 6 or the subcompact 8 often go for quite cheap even for new ones. They are small with -3dB points below 30Hz. They likely won't play super loud but are likely good enough for the M-Audio AV40s.

Thanks for this post - very informative on how to read specs. I will take a good look at what's available.
 
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