# Best small sealed-box sub



## Spasticteapot (Mar 5, 2007)

I want to build a small (ideally 2.5 cubic feet or less) sub that can play to 40hz (preferably an f3 of 35hz, but I'm not picky) and sounds pretty good. SPL is less important than sound quality (although I'd prefer to be able to use a 100w plate amp - no 80db efficiency woofers, please!), and a low price would be good. 

This will be part of a 2.1 system, and crossed over at 80hz.


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## bassfromspace (Jun 28, 2016)

Spasticteapot said:


> I want to build a small (ideally 1 cubic foot or less) sub that can play to 40hz (preferably an f3 of 35hz, but I'm not picky) and sounds pretty good. SPL is less important than sound quality (although I'd prefer to be able to use a 100w plate amp - no 80db efficiency woofers, please!), and a low price would be good.
> 
> This will be part of a 2.1 system, and crossed over at 80hz.


It's impossible to get high efficiency and a small box.

One or the other.

Hoffman's Iron Law.


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## Spasticteapot (Mar 5, 2007)

bassfromspace said:


> It's impossible to get high efficiency and a small box.
> 
> One or the other.
> 
> Hoffman's Iron Law.


Yes, but it's possible to get less-than-appalling efficiency. 86dB is not out of the question.


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## Dangerranger (Apr 12, 2006)

F3 of 35hz in car, or F3 of the system anechoic??? You're not gonna get it from a small sealed box less than a cubic foot honestly.


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## Spasticteapot (Mar 5, 2007)

Dangerranger said:


> F3 of 35hz in car, or F3 of the system anechoic??? You're not gonna get it from a small sealed box less than a cubic foot honestly.


Not in a car. In my room. 

A larger box is OK. I'm just looking for general recommendations.

I hear the Infinity Kappa Perfect 10" is nice.


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## bassfromspace (Jun 28, 2016)

What's your limitation? Are you stuck with that 100 watt amp or is there a maximum enclosure size you want?


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## bassfromspace (Jun 28, 2016)

Will this sub be strictly music or music and HT?


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## Candisa (Sep 15, 2007)

Any reason why you want a sealed box?

I'm thinking Peerless XLS + PR, happy with a small box, decent efficiency, nice deep bass...

greetz,
Isabelle


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## Luke352 (Jul 24, 2006)

How cheap is cheap, JBL W GTI subs can be picked up at a resonable price, sealed in 2.5cuft the f3 is about 37hz, or 2.5 cuft tuned to 30hz gives an F3 about 30hz. I've never tried mine in room, but there are some members who have so they may be able to comment on how they respond in room in that size enclosure. They work brilliantly in 1.6 cuft sealed in car, so I imagine 2.5 sealed in room should be nice.


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## mmbongo (Nov 23, 2007)

An Image Dynamics IDQ12 in 1 cu. ft. sealed would get you -3db at around 25hz and would excel at sound quality.

However you might consider doing an IDQ 12 in a bandpass enclosure to get more SPL, even down to 20hz.

http://imagedynamicsusa.com/manuals/iDQ/iDQ 12 D4 V.3.pdf


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## mmbongo (Nov 23, 2007)

An Image Dynamics IDQ12 in 1 cu. ft. sealed would get you -3db at around 25hz and would excel at sound quality.

However you might consider doing an IDQ 12 in a bandpass enclosure to get more SPL, even down to 20hz.

http://imagedynamicsusa.com/manuals/iDQ/iDQ 12 D4 V.3.pdf


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## Xander (Mar 20, 2007)

I know you said sealed, but what about the Dayton HO 10 in a ported encolsure? Can be quite small and go deep. Porting will increase efficiency, should do fine off a 100 watt amp


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## Oliver (Jun 25, 2007)

These are pretty efficient and very , very cheap [ $25.00 pricetag ]

http://www.diymobileaudio.com/forum/showthread.php?t=45266&page=2


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## FJF (Jul 5, 2007)

mmbongo said:


> An Image Dynamics IDQ12 in 1 cu. ft. sealed would get you -3db at around 25hz and would excel at sound quality.


Agreed. I have an IDQ12V2 in a .88ft^3 enclosure - fantastic SQ. Driven by a Xtant 121M, there's no lack of amplitude when playing music in a mid-size car .


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## Spasticteapot (Mar 5, 2007)

Candisa said:


> Any reason why you want a sealed box?
> 
> I'm thinking Peerless XLS + PR, happy with a small box, decent efficiency, nice deep bass...
> 
> ...


Passive radiators are [email protected]#$ expensive. Otherwise, I'd use one. 

The JBL GTI sounds nice. I'm not a "bass-head", so I don't need much deep bass, or SPL for that matter. The sub is for music, not HT.

The most obvious solution to this problem just hit me in the head - an aperiodic vent. Presuming I can find one, this should allow the use of a very small sub indeed.


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## DS-21 (Apr 16, 2005)

Candisa said:


> Any reason why you want a sealed box?
> 
> I'm thinking Peerless XLS + PR, happy with a small box, decent efficiency, nice deep bass...
> 
> ...


The PR is a bad idea in a moving car. Search to see why.

The ur-XLS12 has a great parameter set for in-car sealed box use.


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## Candisa (Sep 15, 2007)

DS-21 said:


> The PR is a bad idea *in a moving car*.


Maybe you could *read* the start post? He'll use a plate amp, sound like a non-moving room situation to me?

And by the way, tell me why a PR is a bad idea in a car. I'm using PR's in my car, people have been using PR's in their cars, I don't see the problem?

greetz,
Isabelle


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## DS-21 (Apr 16, 2005)

Candisa said:


> Maybe you could *read* the start post? He'll use a plate amp, sound like a non-moving room situation to me?
> 
> And by the way, tell me why a PR is a bad idea in a car. I'm using PR's in my car, people have been using PR's in their cars, I don't see the problem?
> 
> ...


Excuse me for seeing something in a forum called "Mobile Audio Discussion > Product Selection & Comparisons" and expecting it to be about mobile audio!

And the problem with PR's in a car is basically one of durability. It's not a wise thing to constantly jostle about cone with a lot of mass strapped behind it in directions it was never intended to go.


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## Candisa (Sep 15, 2007)

I use 400gr PR's, some subwoofers even have an Mms that's that much. Also, some caraudio brands have pr's (Ground Zero for example).

If a PR with only 400gr on it gets ****ed up in a car, it shouldn't be called a 'PR' but a 'POC', a piece of crap...

greetz,
Isabelle


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## [email protected] (Jun 12, 2008)

DS-21 said:


> Excuse me for seeing something in a forum called "Mobile Audio Discussion > Product Selection & Comparisons" and expecting it to be about mobile audio!
> 
> And the problem with PR's in a car is basically one of durability. *It's not a wise thing to constantly jostle about cone with a lot of mass strapped behind it in directions it was never intended to go*.


its moves in and out whats wrong with that?


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## ItalynStylion (May 3, 2008)

BeatsDownLow said:


> its moves in and out whats wrong with that?


I think the problem is that the mass is at the far end of the cone which gives it a lot more leverage.


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## bmaupin (Feb 22, 2006)

I'm surprised no one has mentioned the Dayton RSS315HF - models an F3 of 37Hz in 2 cubes (making it bigger does not lower F3). 84db/W (87 @ 2.83V).

- Brad


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## thehatedguy (May 4, 2007)

How is it any different than the massive weights strapped behind the cones of a subwoofer?

CA the added weights and they'll never move.

Your arguement makes no sense.




DS-21 said:


> Excuse me for seeing something in a forum called "Mobile Audio Discussion > Product Selection & Comparisons" and expecting it to be about mobile audio!
> 
> And the problem with PR's in a car is basically one of durability. It's not a wise thing to constantly jostle about cone with a lot of mass strapped behind it in directions it was never intended to go.


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## DS-21 (Apr 16, 2005)

thehatedguy said:


> How is it any different than the massive weights strapped behind the cones of a subwoofer?
> 
> CA the added weights and they'll never move.
> 
> Your arguement makes no sense.


Location, for one thing. Where are the weights strapped behind the motion on a mass-loaded sub? Generally somewhere between the surround and the spider, right? Under the dustcap or around the back of the cone. (I'm ignoring that in the modern world mass loading is kind of silly, as it can cause problems - stuck mass rings on a JBL 2235H, anyone? - and does absolutely nothing that EQ can't do as well or better.)

It's a simple matter of polar movement of inertia. You stick a lot of weight on the back of a spider far away from any other locating member, jostle it about repeatedly at angles the suspension wasn't intended to support, and chances are high that a failure will result.

I have a repaired XLS12-PR to prove it. The "former" came completely clear of the spider. And I wasn't using it long term in a car. I merely had the sub on my front seat and drove it about 30 miles.

Now, repairing it in my case was no big deal, and I was able to repair the PR with no detectable loss of function, such that the sub functioned very capably in my nearfield system for quite a while. (It's in my cellar now, but I'm keeping my three XLS12's and PR's for my next home.) But do it often enough or use glue that's too strong and you may well end up with a ripped spider rather than a failed glue joint.


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## Candisa (Sep 15, 2007)

Was that the 290, 425 or 600gr. version and how much mass did you add to that?

If you added mass, did you add a very flat 'washer' with a big diameter, or did you use a more thicker, smaller in diameter mass?

I'm using 3 10" 400gr PR's with no added mass (and I'm sorry I didn't order the 265gr version, because it does fine in a car environment too  )...

On-topic: That Dayton is a good option indeed, I was looking at the 15" version yesterday (maybe those are a good option if I ruine my PR's )

greetz,
Isabelle


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## DS-21 (Apr 16, 2005)

Candisa said:


> Was that the 290, 425 or 600gr. version and how much mass did you add to that?


425gr I believe, massed up to either 625 or with 1050, with the biggest-diameter washers I could fit, and a smaller endcap one.

If you added mass, did you add a very flat 'washer' with a big diameter, or did you use a more thicker, smaller in diameter mass? A lower tuning than the ap note worked better in my system.


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## npdang (Jul 29, 2005)

Sounds like a job for a ported Peerless XLS/XXLS woofer. The enclosure will be small, but port will be big. Hence, they also sell a PR for this app.

If this is more of a budget/space project, I would consider a 6th order bandpass using any good 8" driver. I believe there is a dayton ref 8" sub? Or even any of the TB woofers (although they would not be my first choice). If you're crossing at 80hz, you really only need a very narrow bandwidth from the sub to reach flat response to 20hz in a small room.


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## ItalynStylion (May 3, 2008)

npdang said:


> Sounds like a job for a ported Peerless XLS/XXLS woofer. The enclosure will be small, but port will be big. Hence, they also sell a PR for this app.
> 
> If this is more of a budget/space project, I would consider a 6th order bandpass using any good 8" driver. I believe there is a dayton ref 8" sub? Or *even any of the TB woofers* (although they would not be my first choice). If you're crossing at 80hz, you really only need a very narrow bandwidth from the sub to reach flat response to 20hz in a small room.


Yesssssss...you know you want to! Throw some 6.5" subs in a tiny ass box ported LOW and see what they can do. Not the most qualified candidate but certainly the most fun


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## Candisa (Sep 15, 2007)

DS-21: I'm using 400gr 10" PR's and I regret I didn't buy the 265gr versions. Lower tuning in a normal PRed box would work better in a car, but I'm building a 6th order bandpass enclosure with the PR's in the low chamber and a slot port in the high chamber. This way, the curve is boosted around 50Hz in stead of lowered around 20Hz, so I get a similar curve compared with a lower tuned PRed box, but with more output.

I wouldn't mass a PR up to 1000gr in a car because of the problem you warned me about, that's why I chose the option that doesn't need heavy PR's. I don't expect trouble with a 400gr PR.

greetz,
Isabelle


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